an experimental investigation of structural composite lumber … · 2020-01-20 · lumber (lvl),...

AN EXPERIMENTAL INVESTIGATION OF STRUCTURAL COMPOSITE

LUMBER LOADED BY A DOWEL IN PERPENDICULAR TO GRAIN

ORIENTATION AT YIELD AND CAPACITY

by

David Edward Finkenbinder

Thesis submitted to the faculty of the

Virginia Polytechnic Institute and State University

in partial fulfillment of the requirements for the degree of

MASTER OF SCIENCE

in

CIVIL ENGINEERING

Dr. Daniel P. Hindman, Co-Chair

Dr. W. Samuel Easterling, Co-Chair

Dr. Joseph R. Loferski

Dr. Surot Thangjitham

September 4, 2007

Blacksburg, Virginia

Keywords: Wood Connections, Monotonic Loading, Capacity, Laminated Veneer

Lumber, Parallel Strand Lumber

AN EXPERIMENTAL INVESTIGATION OF STRUCTURAL COMPOSITE

LUMBER LOADED BY A DOWEL IN PERPENDICULAR TO GRAIN

ORIENTATION AT YIELD AND CAPACITY

by

David Edward Finkenbinder

Abstract

The research summarized by this thesis was comprised of an experimental

analysis of beams loaded perpendicular to grain at midspan by a bolted double-shear

laterally-loaded connection. Connection specimens were loaded monotonically until

capacity was reached. Variables of consideration included the loaded edge distance of

the connection main member, the span:depth ratio of the main member, and the main

member material. Southern pine machine-stress-rated (MSR) lumber, laminated veneer

lumber (LVL), and parallel strand lumber (PSL) were the three material types included in

the program.

Experimental results were compared with theoretical predictions from three

models: the yield theory-based general dowel equations, which are currently the standard

for laterally-loaded connection design in the U.S., and two models based upon fracture

mechanics. All material property inputs required by the three models, were measured in

the experimental program of this research and used to produce theoretical predictions.

Comparisons were also made with respect to design values in the form of calculated

factors of safety, over-strengths, and design factors of safety.

Test results and observed trends are provided for all connection and material

property tests. Notable trends included failure by splitting for all connections at low

loaded edge distances, and variable span:depth ratios generally having a negligible effect

on both connection and model performance. In most cases, the general dowel equations

were more accurate than the two fracture models, however it should be noted that all

three models over-predicted connection capacity at low loaded edge distances.

Acknowledgements

This research has been a product of collaboration with faculty and graduate

students from Virginia Tech and other universities, contributors of financial and material

support, members of industry and the general wood engineering community.

I would like to express my sincerest gratitude to Dr. Daniel P. Hindman and Dr.

Joseph R. Loferski for their guidance, wisdom, and consistent encouragement throughout

this project. I would also like to thank Dr. W. Samuel Easterling and Dr. Surot

Thangjitham, who served on my committee and provided their expertise as needed.

I am indebted to the Wood-Based Composites Center and Weyerhaeuser for

financially supporting myself and this project. I am grateful to Timber Truss Housing

Systems for their donation of MSR lumber, which was essential to the successful

accomplishment of my research objectives.

Special recognition must also be directed to the staff of the Brooks Forest

Products Center, who offered their talents and dedication to assist whenever needed,

without hesitation. My deepest gratitude must be expressed to Rick Caudill, Kenny

Albert, David Jones, Angela Riegel, and Linda Caudill – your friendship has been equally

invaluable.

I am deeply appreciative of the helpful correspondance and oversight that I have

received from numerous researchers. I must recognize Phil Line from the American

Forest & Paper Association, and David Gromala from Weyerhaeuser, who have provided

critical oversight towards the direction of this work. Additional gratitude is expressed to

Monica Snow from UNB, Drs. James D. Dolan and David Carradine from WSU, David

Kretschmann and Douglas Rammer from the FPL, and Dennis Schoenmakers from

TUDelft. I am also grateful for the recommendations and commentary offered to me by

the following Hokie graduates: Jason Smart, S. Kate Harrison, Tom Ramskill, and Dustin

Albright.

I would also like to thank my friends and colleagues from the Structural

Engineering & Wood Science Departments. I express deep gratitude to Andrew

Burkholder and Chris Wilson for offering an easy-going perspective during stressful

times; to Archibald Wilson, Brett Leedy, and Hunter Hodges for never turning down an

adventure in the outdoors; to Gi Young Jeong and Zhiyuan Lin for spending as much

iii

time at the office as I have, and to Susan Bowers, for offering an exceptional amount of

support and encouragement. You have made my time in Blacksburg a pleasure.

This work would not have been possible without the love and support offered by

my family. I am thankful for the encouragement provided by my sister, Jennifer, and my

brother, Matthew. Most importantly, I want to thank my parents for their love, patience,

support, and inspiration in my life and studies.

Finally, I would like to dedicate this work to the memory of the Hokies lost earlier

this year while seeking to advance their education. I feel strongly that my most valuable

lesson learned while in Blacksburg has been a better appreciation for the value of life.

iv

Table of Contents List of Figures ix

List of Tables xii

Chapter 1 – Introduction 1

1.1 – Background 1

1.2 – Objectives 3

1.3 – Significance 3

Chapter 2 – Literature Review 4

2.1 – Introduction 4

2.2 – Current U.S. Connection Design Methodology 4

2.2.1 – Succession of Design Methodologies 4

2.2.2 – Research Relating to Embedment Strength 6

2.2.3 – 2005 NDS Design Methodology 8

2.2.3.1 – Allowable Stress Design for Wood Connections 13

2.2.3.2 – Reliability-Based Design for Wood Connections 15

2.3 – Fracture Mechanics-Based Models 17

2.3.1 – Van der Put Model 18

2.3.2 – Jensen Model 21

2.3.3 – Eurocode 5 (EC5) Splitting Capacity 22

2.4 – Current Reliability-Based Design State of the Art 24

2.5 – Summary 25

Chapter 3 – Materials and Methods 26

3.1 – Introduction 26

3.2 – Materials 27

3.3 – Sample Size Determination 28

3.4 – Connection Tests 28

3.4.1 – Introduction 28

3.4.2 – Specimen Preparation 29

3.4.3 – Specimen Identification 32

3.4.4 – Connection Layout 32

3.4.5 – Connection Testing Procedure 35

v

3.5 – Material Tests 41

3.5.1 – Shear Modulus Tests 42

3.5.2 – Modulus of Elasticity Tests 44

3.5.3 – Dowel Embedment Tests 47

3.5.4 – Bolt Bending Strength Tests 49

3.5.5 – Tension Perpendicular to Grain Tests 52

3.5.6 – Mode I Fracture Tests 53

3.5.7 – Moisture Content and Specific Gravity Tests 57

3.6 – Property Definitions 57

Chapter 4 – Results and Discussion 60

4.1 – General 60

4.2 – Connection Tests 60

4.2.1 – Connection Test Subset – Continuously Supported Case 73

4.3 – Material Property Tests 74

4.3.1 – Shear Modulus Tests 75

4.3.2 – Modulus of Elasticity Tests 75

4.3.3 – Dowel Embedment Tests 76

4.3.4 – Bolt Bending Strength Tests 78

4.3.5 – Tension Perpendicular to Grain Tests 79

4.3.6 – Mode I Fracture Tests 80

4.3.7 – Moisture Content and Specific Gravity Tests 81

4.4 – Evaluation of TR-12 82

4.4.1 – TR-12 Theoretical Lateral Connection Resistance Values 82

4.4.2 – Comparison of Theoretical (Calculated) Values to

Test Values 85

4.4.2.1 – Comparisons with Variable Span:Depth Ratios 85

4.4.2.2 – Comparisons with Variable Loaded Edge Distance

87

4.4.2.3 – Comparisons with Variable Material 88

4.4.2.4 – Continuously Supported Subset 90

4.4.3 – Design Value Comparison 91

vi

4.5 – Evaluation of Fracture Models 94

4.5.1 – Fracture Model Theoretical Lateral Connection

Resistance Values 95

4.5.2 – Comparison of Theoretical (Calculated) Values to

Test Values 96

4.5.2.1 – Comparisons with Variable Span:Depth Ratios 96

4.5.2.2 – Comparisons with Variable Loaded Edge Distance

98

4.5.2.3 – Comparisons with Variable Material 99

4.5.2.4 – Continuously Supported Subset 101

4.5.3 – Design Value Comparison 101

4.6 – Comparisons Between TR-12 and Fracture Models 102

Chapter 5 – Summary and Conclusions 107

5.1 – Summary 107

5.2 – Conclusions 108

5.2.1 – Connection Test Results 108

5.2.2 – Material Property Tests Results 108

5.2.3 – Analysis of TR-12 Performance and Design Value

Comparisons 109

5.2.4 – Analysis of Van der Put Model and Jensen Model

Performance 109

5.2.5 – Comparison of TR-12, Van der Put, and Jensen Models 110

5.2.6 – Conclusions Regarding Importance of Inputs into

Model Equations 110

5.3 – Limitations 111

5.4 – Recommendations for Future Work 111

References 113

Appendix A – Connection Test Load-Displacement Curves 119

Appendix B – Connection Test Data 131

Appendix C – TR-12 Calculations (with Inputs) 138

Appendix D – Fracture Calculations (with Inputs) 150

vii

Appendix E – Material Property Test Data 158

Vita 181

viii

List of Figures

Figure 2-1: Yield Modes for Double-Shear Dowel-Type Connections

(after Breyer et al. 2003) 9

Figure 2-2: Fracture Modes Considered by Linear Elastic Fracture Mechanics

(after Jorissen 1998) 18

Figure 3-1: Experimental Design Flow Chart – Succession of Testing 26

Figure 3-2: Schematic of Connection Specimen Dimensions 29

Figure 3-3: Connection Layout Diagram 33

Figure 3-4: Connection Fixture Side Plates 34

Figure 3-5: Connection Fixture – (a) Side View – (b) Top View 35

Figure 3-6: Simply Supported Connection Specimen with Lateral Supports 36

Figure 3-7: LVDT Configuration Diagram 37

Figure 3-8: LVDT 1 and 2 Installation Detail 38

Figure 3-9: LVDT 3 and 4 Installation Detail 39

Figure 3-10: LVDT 5 Installation Detail 39

Figure 3-11: LVDT 6 Installation Detail 40

Figure 3-12: Typical Locations of Specimens Removed from a Tested

Connection Specimen – a.) Center Block, b.) Dowel Embedment

Specimen, c.) Tension Perpendicular to Grain Specimen, d.) Mode I

Fracture Specimen, e.) Moisture Content and Specific Gravity Specimen 42

Figure 3-13: ASTM D 198 Torsion Test Setup with Specimen

(after Harrison 2006) 43

Figure 3-14: Three-Point Bending Test Configuration (Harrison 2006) 45

Figure 3-15: ASTM D 5764-97a Full-Hole Dowel Embedment Strength

Specimen 48

Figure 3-16: ASTM D 5764-97a Dowel Embedment Test Setup 49

Figure 3-17: Cantilever Bending Test Method Schematic

(after Albright 2006) 50

Figure 3-18: Bolt Bending Test Setup 51

ix

Figure 3-19: ASTM D 193 Tension Perpendicular to Grain Specimen

and Test Setup 53

Figure 3-20: Fracture Specimen Dimensions (LVL Cross Section Shown)

(after Ramskill 2002) 55

Figure 3-21: Typical Fracture Specimen 56

Figure 3-22: Fracture Test Fixture (Shown with PSL Specimen) 56

Figure 3-23: Representative Load-Slip Curve, with Calculated Values

(after Smart 2002) 58

Figure 4-1a: Main Member of Typical Mode S Failure 61

Figure 4-1b: Main Member of Typical Mode Is-S Failure 61

Figure 4-1c: Bolt of Typical Mode IIIs-S Failure 62

Figure 4-1d: Main Member of Typical Mode IIIs-S Failure 62

Figure 4-2: Representative Specimen with Splitting Propagation

Highlighted (MSR Shown) 64

Figure 4-3: Capacity Resistance vs. 5% Offset Yield Resistance, with Linear

Regressions (after Smart 2002) 66

Figure 4-4: Average Load-Displacement Plots for MSR Connections

with 4D Loaded Edge Distance and Variable Main Member

Span:Depth Ratio 68

Figure 4-5: Average Load-Displacement Plots for LVL Connections


Span:Depth Ratio 69

Figure 4-6: Average Load-Displacement Plots for PSL Connections


Span:Depth Ratio 69

Figure 4-7: Average Load-Displacement Plots for MSR Connections

with 5:1 Main Member Span:Depth Ratio and Variable

Loaded Edge Distance 70

Figure 4-8: Average Load-Displacement Plots for LVL Connections


x


Figure 4-9: Average Load-Displacement Plots for PSL Connections



Figure 4-10: Average Load-Displacement Plots for Connections

with 5:1 Main Member Span:Depth Ratio, 4D Loaded Edge

Distance and Variable Main Member Material 71







Figure 4-13: Bolt and Main Member of Typical Mode IIIs Failure 73

Figure 4-14: Comparison of Model C/T Ratios for Connections

with 5:1 Span:Depth Ratios 105

xi

List of Tables

Table 3-1: Test Configurations and Replications for Connection Testing 30

Table 3-2: Specimen Lengths for Varying Span:Depth Ratios 31

Table 3-3: Lengths of Varying Loaded Edge Distances 31

Table 3-4: LVDT Descriptions and Locations 37

Table 4-1: Failure Modes Observed During Connection Testing

(after Smart 2002) 63

Table 4-2: Average Splitting Lengths with Associated COVs 64

Table 4-3: Average 5% Offset Yield and Capacity Resistance Values,

with Associated COVs 65

Table 4-4: Average Elastic Stiffness, Connection Slip at 5% Offset Yield and

Capacity, and Ductility Datio, for Connection Test Groups 67

Table 4-5: Failure Modes Observed During Continuously Supported

Connection Testing (after Smart 2002) 74

Table 4-6: Average 5% Offset and Capacity Resistance Values, with

Associated COVs, for Continuously Supported Connection Specimens 74

Table 4-7: Average Shear Modulus and Associated COVs 75

Table 4-8: Average Modulus of Elasticity and Associated COVs 76

Table 4-9: Average Dowel Embedment Strengths and Associated COVs 78

Table 4-10: 5% Offset Yield Embedment Strengths – Average Test Values,

NDS Predicted Values, and Ratio Comparisons of NDS Predicted

Values to Average Test Values 78

Table 4-11: Bending Yield Strength (Fyb) Results 79

Table 4-12: Average Tensile Strengths Perpendicular to Grain ( ) tf

and Associated COVs 80

Table 4-13: Average Mode I Fracture Energy (GIf) and Associated COVs 80

Table 4-14: Average Moisture Content and Specific Gravity Results, with

Associated COVs 81

Table 4-15: Average TR-12 Lateral Connection Resistance Values at

xii

5% Offset Yield and Capacity, with Associated COVs 83

Table 4-16: NDS ASD Lateral Design Values (Defined as Minimum of RLDV

and Allowable Shear Check – Shown in Bold) 84

Table 4-17: Average TR-12 C/T Ratios, Associated COVs, and Statistical

Comparisons for MSR Connection Sets with Variable Span:Depth

Ratio (with Detected Statistical Differences Highlighted) 86


Comparisons for LVL Connection Sets with Variable Span:Depth



Comparisons for PSL Connection Sets with Variable Span:Depth



Comparisons for MSR Connection Sets with Variable Loaded Edge

Distance (with Detected Statistical Differences Highlighted) 87


Comparisons for LVL Connection Sets with Variable Loaded Edge



Comparisons for PSL Connection Sets with Variable Loaded Edge



Comparisons for Connection Sets with 4D Loaded Edge Distance and

Variable Material Type (with Detected Statistical

Differences Highlighted) 89


Comparisons for Connection Sets with 7D Loaded Edge Distance

and Variable Material Type (with Detected Statistical



Comparisons for Connection Sets with 10D Loaded Edge Distance

xiii

and Variable Material Type (with Detected Statistical


Table 4-26: Average TR-12 C/T Ratios and Associated COVs, for Continuously

Supported Connections with 4D Loaded Edge Distance 90

Table 4-27: Average TR-12 C/T Ratios and Associated COVs, for Continuously


Table 4-28: Average Factor of Safety, Over-Strength, and Design Factor of Safety

Values, with associated COVs 93

Table 4-29: Average Fracture Lateral Connection Resistance Values at Capacity, with

Associated COVs 95

Table 4-30: Eurocode 5 Design Splitting Capacities 96

Table 4-31: Average Fracture C/T Ratios, Associated COVs, and Statistical

Comparisons for MSR Connection Sets with Variable Span:Depth



Comparisons for LVL Connection Sets with Variable Span:Depth



Comparisons for PSL Connection Sets with Variable Span:Depth



Comparisons for MSR Connection Sets with Variable Loaded Edge



Comparisons for LVL Connection Sets with Variable Loaded Edge



Comparisons for PSL Connection Sets with Variable Loaded Edge



xiv

Comparisons for Connection Sets with 4D Loaded Edge Distance and Variable

Material Type (with Detected Statistical Differences Highlighted) 100







Table 4-40: Average Fracture C/T Ratios and Associated COVs, for Continuously


Table 4-41: Average Fracture C/T Ratios and Associated COVs, for Continuously


Table 4-42: Average EC5 Design Factor of Safety Values, with

associated COVs 102

Table 4-43: Statistical Comparisons between TR-12, Van der Put,

and Jensen C/T Ratios – MSR Connections

(with Detected Statistical Differences Highlighted) 103


and Jensen C/T Ratios – LVL Connections



and Jensen C/T Ratios – PSL Connections


xv

Chapter 1 - Introduction 1

Chapter 1: Introduction 1.1 Background

The wide use of wood in structural applications continues today due to the

benefits it presents in terms of cost, availability as a renewable material and its

remarkable strength to weight ratio. In light-frame construction the traditional material,

solid-sawn dimension lumber, is being increasingly replaced by structural composite

lumber (SCL). These engineered wood products include laminated veneer lumber

(LVL), parallel strand lumber (PSL), and laminated strand lumber (LSL). Other sources

including Smulski (1997) and Harrison (2006) provide detailed descriptions of SCL

products, specifications, and manufacturing processes.

The development and use of SCL is growing for a number of reasons. While the

general industry trend is a decreased availability of larger-diameter timber, SCL is

manufactured from smaller-diameter timber. In comparison to its solid-sawn parent

material, SCL products have greater strength and stiffness properties, and can be

manufactured into any practical uniform cross-sectional dimension and length. These

improved mechanical characteristics also make SCL products more desirable considering

that the growing focus on dynamic loading and vibrations has resulted in a reduction of

recommended span lengths for dimension lumber in structural design codes (Williams

1999).

For the continued growth and sustained use of SCL in structural applications, a

comprehensive understanding of the material properties and behavior is required.

Especially important are connections, which are critical to the integrity and stability of

any structure. In addition to developing the load path between the structural members,

connections also serve as the predominant source of ductility for wood structural systems.

The most common components of structural wood connections are laterally loaded

dowel-type fasteners, such as nails, bolts and screws. In particular, bolts are commonly

used because of their relative ease of installation and capacity to transfer loads.

The current design methodology in the United States for connections in wood

follows the general dowel equations, which appear in simplified form in the provisions of

the National Design Specification for Wood Construction (NDS) (AF&PA 2005). A

fundamental assumption of these equations, which are based upon yield theory, is that the


connection will exhibit ductile behavior up to the achievement of capacity resistance,

characterized by either crushing of the member, yielding of the fastener, or a combination

of the two phenomena. Premature brittle failure, i.e. splitting or cracking of the wood

member, is accounted for by two provisions: 1) fastener spacing requirements, and 2) an

additional check of member stresses. Fastener spacing requirements are defined as

multiples of the bolt diameter and include minimum end distances, edge distances, and

minimum distances between fasteners in multiple-fastener connections. Member stress

checks include shear design in the case of perpendicular to grain connections, and local

stress checks for multiple fastener connections

Two design formats are included in the NDS: allowable stress design (ASD), and

load and resistance factor design (LRFD). Currently, LRFD connection design is based

on a ‘soft-conversion’ from ASD connection design. ASD design values are based upon

5% offset yield level resistances. Interest in capacity-based (LRFD) design of laterally

loaded connections in wood, similar to the design procedures already established in

reinforced concrete and steel, is growing due to the advantages that strength-based design

has over ASD. LRFD permits a structure to be designed with a defined reliability. Also,

strength design puts greater emphasis on the failure mode of the system, allowing for

ductility considerations which are critical in cyclic or dynamic loading conditions.

A majority of validation studies have been focused at the 5% offset yield level

resistance, with less consideration given to behavior at capacity resistance. Further

research of connection behavior at capacity is needed to validate the application of the

general dowel equations at capacity, and to make possible the calibration of LRFD on a

reliability basis. Perpendicular to grain connections, particularly have been identified as

a priority critical to the advancement of LRFD (Smith and Foliente 2002).

The research presented in this thesis is designed to supplement knowledge on the

behavior of perpendicular to grain connections in solid wood and SCL members, at

capacity. It should be noted that prior research of perpendicular to grain connections,

have found splitting behavior to be common, even when using proper spacing

considerations. Therefore, in addition to analyzing the accuracy of the yield theory-based

general dowel equations of the NDS, two simple analytical models based on fracture

mechanics were also included in analysis. These models, the Van der Put model (Van


der Put and Leijten 2000) and the Jensen model (Jensen et al. 2003), were specifically

derived for the prediction of splitting capacity of perpendicular to grain connections.

1.2 Objectives

The principle focus of this research project was to investigate the capacity

behavior and characteristics of laterally-loaded bolted connections in parallel strand

lumber and laminated veneer lumber compared to solid-sawn lumber. The specific

objectives were:

1) Collect physical data on the behavior and mechanics of beams loaded

perpendicular-to-grain at midspan by a bolted double-shear laterally

loaded connection, with solid-sawn dimension lumber, laminated veneer

lumber, and parallel strand lumber main members, up to capacity.

2) Quantify the accuracy of the general dowel equations (TR-12) (AF&PA

1999) in predicting 5% offset load, capacity, and failure mode, using

experimental results from Objective 1).

3) Quantify the accuracy of the fracture mechanics models of Van der Put &

Leijten (2000), and Jensen et al. (2003), using experimental results from

Objective 1).

1.3 Significance

The experimental testing conducted in the first objective of this research would

provide a better understanding of the behavior of connections at conditions of capacity

and fracture, and also provide a direct comparison between solid-sawn dimension lumber

and two types of structural composite lumber. Such behavior would be quantified in the

form of load-slip curves, capacity resistance and slip, elastic stiffness, and ductility ratios.

The second objective, comparison of experimental data with predictions of the

general dowel equations, would lend insight into the adequacy of these equations for

connections at capacity. The third objective would analyze the potential use of fracture

mechanics models to predict splitting strength of solid-sawn dimension lumber and SCL.

Direct comparisons between the results from the second and third objectives, would also

yield insight into which modeling approach best predicts connection capacity.


Chapter 2: Literature Review

2.1 Introduction

This literature review summarizes the progression and current state of lateral

connection design methodology as given by the NDS. Both design format options, ASD

and LRFD, will be presented. In addition, two fracture models will be presented, which

offer two viable alternatives for the prediction of capacity resistance of perpendicular to

grain connections. A summary of the state-of-the-art of reliability-based design of

connections will also be provided.

2.2 Current U.S. Connection Design Methodology

Wood structures are currently designed according to the National Design

Specification for Wood Construction – ASD/LRFD (NDS) (AF&PA 2005), by one of

two formats: allowable stress design (ASD) or load and resistance factor design (LRFD).

Lateral connection design for both formats is based upon the European Yield Model,

which will be described in this section. Prior to the 2005 edition of the NDS, the NDS

manual contained only the ASD format, and a separate manual contained the LRFD

format. The origin, supporting research, and design values pertaining to these two

formats, will also be presented in this section.

2.2.1 Succession of Design Methodologies

The initial design methodology for laterally loaded single fastener dowel-type

connections was based off of empirical equations derived from monotonic experimental

testing of bolted timber connections by Trayer (1932). This research was the first

significant investigation in the U.S. of design values for bolted connections, and also

introduced the concept of basing design from the proportional limit of the connection

load-displacement behavior. Included with the work was the identification of geometric

requirements, meant to limit the occurrence of premature splitting before the achievement

of design-level resistances, in the form of end distance, edge distance, and bolt spacings.

Subsequent experimental investigations of bolted connections, conducted by Doyle and

Scholten (1963), and Soltis et al. (1986), have supported the accuracy of the empirical


equations formulated by Trayer (1932). Although a fundamental limitation of this design

method was its basis on a finite number of connection materials and configurations, it

served as the NDS protocol for laterally-loaded dowel-type connection design, through

the 1986 edition.

An entirely different methodology for the design of laterally-loaded dowel type

connections was introduced by Johansen (1949), known as the yield model or European

Yield Model (EYM). The model facilitated prediction of connection resistance on the

principle assumptions of ideal elastic-plastic behavior of the steel dowel and wood

connection members, connectors loaded laterally with no gap present between members,

negligible friction, and failures consisting of either an embedment failure below the

dowel, one or two plastic hinges forming in the dowel, or a combination of the two

mechanisms. Dowel embedment strength of the connection members, dowel bending

strength, and geometry factors of the connection, were the key inputs of the model. Its

accuracy in predicting monotonic yield resistance has been validated by the research of

McLain and Thangjitham (1983), Aune and Patton-Mallory (1986), and Soltis and

Wilkinson (1987), amongst others. Yield theory has been the basis of design for

laterally-loaded dowel connections, since first being included in the 1991 NDS (Breyer et

al. 2003). A more detailed description of the model as it appears in the NDS, is provided

in Section 2.2.3.

Several models have been created more recently that extend prediction

capabilities to include connection slip, and hysteretic considerations that permit the

analysis of dynamic loads. The culmination of these efforts has been the load-slip model

presented by Heine (2001), a model based upon elements of yield theory, non-linear

response, and hysteresis elements selected from a genetic algorithm. The model also

included an embedded stochastic model, allowances for system slack (i.e. oversized

dowel holes) and a novel failure model termed the ‘Displaced-Volume-Method’. The

model, instituted inside a computer program, was validated with experimental data of

single and multiple-fastener, parallel to grain connections.


2.2.2 Research Relating to Embedment Strength

Embedment strength is an input included in all three models mentioned in Section

2.2.1. As such, much research pertaining to connection performance has concentrated on

the relationship between embedment strength and the following variables: “angle

between loading and grain direction, loading rate and/or duration, bolt angle with respect

to load direction, bolt hole oversize, specific gravity, and moisture content” (Smart 2002).

With respect to grain orientation, research has shown that embedment strength

perpendicular to grain is generally lower than parallel to grain, once past a critical dowel

diameter (the two orientations are approximately equal for lower diameters). Soltis et al.

(1987) found that for bolts, which typically have diameters exceeding 0.25 in.,

perpendicular to grain embedment strengths were significantly lower than respective

values from the parallel to grain orientation. For the case of intermediate loading angles,

where the angle of loading lies between the parallel and perpendicular to grain

orientation, the Hankinson formula is used to quantify embedment strength. The formula

is the following (Breyer et al. 2003):

θθθ 22 cossin ⊥

⊥

+=

eell

eelle FF

FFF (2-1)

Where,

Feθ = Embedment strength at angle of load θ, psi.

Fell = Embedment strength, parallel to grain, psi.

Fe ⊥ = Embedment strength, perpendicular to grain, psi.

Considerable research has also been directed towards the relationship between

embedment strength and moisture content, which has been summarized by Rammer and

Winistorfer (2001). Results of such work have concluded that embedment strength

increases whenever moisture content decreases, and vice versa. Separate studies have

found a relationship existing as a function of moisture content, between embedment

strength and specific gravity. The specific relationship at 12% moisture content for

softwoods (the typical equilibrium moisture content assumed for normal service


conditions in wood construction), was determined for common bolt diameters by

Wilkinson (1991) to be:

Fell = 11200G (2-2)

Fe ⊥ = 6100G1.45/√D (2-3)

Where,

G = specific gravity or equivalent specific gravity (see below)

D = dowel diameter, in.

Equivalent specific gravity (ESG) is used in lieu of actual specific gravity, to

facilitate the application of Equations 2-2 and 2-3 to SCL products. The specific ESG

value for a SCL product is determined by inserting the test embedment strength (and

dowel diameter for Equation 2-3) into the above equations, and solving for the

corresponding specific gravity (Johnson and Woeste 2000). ESG values are typically

included with the manufacturer’s design literature for each SCL product.

Time-dependent (also referred to as duration of load or DOL) effects have also

been studied, and efforts have been summarized by Rosowsky and Reinhold (1999).

Studies have shown that embedment strength values, and most other wood properties in

general, are generally higher for shorter duration loads. However the connection-specific

DOL testing program of Rosowsky and Reinhold (1999) revealed no significant trend

tied to connection performance and load duration. Gutshall (1994) cyclically tested nail

and bolted connections, and concluded that DOL adjustments were appropriate for

seismic and wind loading conditions.

Studies have also considered the relationship between the connection dowel hole

(bolt hole in the case of this research) and embedment strength. The importance of holes

being properly drilled was highlighted by Goodell and Phillips (1944), who found that

roughly-drilled holes afforded reduced connection resistances, in comparison with

smooth holes. Considerations to hole oversizing, which is typical of bolt holes to provide

assembly tolerance and to minimize splitting during connection fabrication, were given in

the work of Wilkinson (1993). The work did not find oversizing itself to be a strength

limiting practice (Smart 2002).


With the growing usage of structural composite lumber in wood structures, the

research of Carstens (1998) addressed the need to investigate embedment strength values

of engineered wood composites, and compare the two ASTM standards that exist for the

measurement of embedment strength. Findings yielded good agreement with the

previous study of Wilkinson (1991). It was also noted that composites typically had

higher embedment strengths in comparison with lumber of the same species, for both

principle orientations (Carstens 1998).

2.2.3 2005 NDS Design Methodology

As mentioned previously, both of the current design methodologies (ASD and

LRFD) for laterally-loaded dowel-type connections are based from the European Yield

Model, which uses a strength-of-materials approach and assumptions as described in

Section 2.2.1. General design provisions for mechanical connections are given in

Chapter 10 of the NDS, and specific provisions for dowel connections are given in

Chapter 11 (AF&PA 2005).

For double shear connections, there are a total of 3 yield limit modes, and 4 yield

mechanisms (Figure 2-1). Mode I failure is characterized by embedment failure in either

the main (denoted as mode Im) or the side members (denoted as mode Is), with no

presence of dowel bending or rotation. Mode IIIs failure is characterized by the

formation of a plastic hinge in the fastener at each shear plane of the connection, and

localized crushing of at least one of the members. Mode IV failure is characterized by

the formation of two plastic hinges at each shear plane of the connection, and localized

crushing of at least one of the members (Breyer et al. 2003). A schematic of these yield

modes is shown in Figure 2-1.


Mode Im Mode Is

Mode IIIs Mode IV

Figure 2-1: Yield Modes for Double-Shear Dowel-Type Connections (after Breyer et al.

2003)

Each yield mechanism has a corresponding yield equation that is derived from the

connection geometry and assumed failure mechanism. The potential presence of

intermember gap, and fastener moment resistance are also considered in the derivation.

However, it should be noted that the effects of end fixity at the interface of the fastener

head and the side member, the contribution of withdrawal resistance from the fastener,

and the contribution of friction between members of the connection, are not included in

the yield equations. The governing load is the minimum predicted load from the set of

yield equations. Assuming the fulfillment of spacing requirements, the yield mode that

corresponds with the minimum predicted load, is the connection behavior expected up to

the achievement of capacity resistance. Behavior at failure can differ significantly

however, including possible “splitting along a line of fasteners, formation of a shear plug,

fastener shear, and or fastener withdrawal” (AF&PA 1999).

These general yield equations (or general dowel equations) are given by the

General Dowel Equations for Calculating Lateral Connection Values – Technical Report

12 (AF&PA 1999), also commonly referred to as TR-12, are shown as Equations 2-4

through 2-7. Values at the proportional limit, 5% offset yield load, and capacity limit


states can be determined, by inserting the dowel embedment strength and dowel

embedment strength values for the desired limit state. TR-12 does not, however, provide

for failure load predictions, which are typically defined as 80% of capacity or the load at

a given deflection limit (AF&PA 1999).

mmlqP =Im (2-4)

ssIs lqP 2= (2-5)

⎟⎟⎠

⎞⎜⎜⎝

⎛+

⎟⎟⎠

⎞⎜⎜⎝

⎛−−⎟⎟

⎠

⎞⎜⎜⎝

⎛+−⎟

⎠⎞

⎜⎝⎛ ++−−

=

ms

mss

ms

ss

IIIs

qq

Mlqqq

glgl

P

21

41

421

414

22

22

(2-6)

( )

⎟⎟⎠

⎞⎜⎜⎝

⎛+

−−⎟⎟⎠

⎞⎜⎜⎝

⎛+−+−

=

ms

msms

IV

qq

MMqq

ggP

21

21

21

2142

(2-7)

where,

P = nominal lateral connection value, lb.

ls = side member dowel bearing length, in.

lm = main member dowel bearing length, in.

qs = side member dowel bearing resistance = FesD, lb/in.

qm = main member dowel bearing resistance = FemD, lb/in.

Fes = side member dowel embedment strength, psi.

Fem = main member dowel embedment strength, psi.

g = gap between members, in.

D = dowel shank diameter, in.

Fb = dowel bending strength, psi.

Ds = dowel diameter at maximum stress in side member, in.

Dm = dowel diameter at maximum stress in main member, in.

Ms = side member dowel moment resistance = Fb(Ds3/6), in.-lb.

Mm = main member dowel moment resistance = Fb(Dm3/6), in.-lb.


To determine reference lateral design values, a form of the general yield equations

appear in Chapter 11 of the NDS. Due to several key differences (the exclusion of inter-

member gap and fastener moment resistance) however, they are formally referred to as

yield limit equations. The equations apply to the 5% offset yield limit state, a value

which occurs between the proportional limit and capacity resistance.

Section 11.3.2 of the NDS allows for 5% offset yield dowel embedment strength

to be calculated from Equations 2-2 and 2-3, provided the dowel diameter is greater than

0.25 in. Assigned specific gravity values are listed in NDS Table 11.3.2A for most

common varieties of visually graded lumber, MSR lumber, and machine evaluated

lumber. Equivalent specific gravity values for structural composite lumber are typically

provided in manufacturer design literature (AF&PA 2005).

To achieve full lateral design values, spacing requirements exist to prevent against

premature splitting of the connection (it should be noted that the spacing requirements are

based upon those initially specified by Trayer (1932)). These values are given in NDS

Section 11.5, and include edge distance requirements, end distance requirements, and

spacing requirements for multiple fastener connections. The spacing requirements that

pertain to the scope of this research are as follows (listed as a function of dowel diameter,

D) (AF&PA 2005):

• Edge distance (perpendicular to grain connections):

o Loaded edge – 4D

o Unloaded edge – 1.5D

• End distance (perpendicular to grain connections):

o 4D

It should be noted, that the NDS explicitly states that a ‘heavy or medium

concentrated loads shall not be suspended below the neutral axis of a single sawn lumber’

beam, unless ‘reinforcement is provided to resist tension stresses perpendicular to grain’

(AF&PA 2005). At capacity level connection loading conditions, an example of a

violation of this condition would be any case with a 1/2 in. diameter dowel loading a

beam with a loaded edge distance of 2 in., in a member exceeding 4 in. of depth.

However, correspondence with Line (2007) has revealed that this case is unavoidable in

practice due to common multiple fastener configurations, and situations that incur a stress


reversal in the connection member (which reverses the loaded and unloaded edge

distances) (Line 2007).

Provisions are also given on the correct over-sizing with regards to bolt diameter.

Specifically, holes are to be within 1/32 in. and 1/16 in. larger than the bolt diameter.

Additionally, bolts are not to be installed forcibly into the bolt hole, as this can

potentially damage the hole (AF&PA 2005).

According to NDS 10.1.2, in addition to designing according to connection

strength by means of the determining the reference lateral design value (the minimum of

resistances obtained from the yield limit equations), structural members themselves must

be checked for their load-carrying capacity. Specifically, in the case of a beam loaded

perpendicular to grain by a connection, this check comes in the form of calculating an

allowable design shear (NDS 3.4.3). For conditions where the connection is located less

than a distance equal to five member depths from the end of the member, allowable

design shear is the following (AF&PA 2005): 2

''

32

⎥⎦

⎤⎢⎣

⎡⎥⎦⎤

⎢⎣⎡=

dd

bdFV eevr (2-8)

where,

= design shear, adjusted, lb. 'rV

= design shear parallel to grain value, adjusted, psi. 'vF

b = width of member, psi.

de = loaded edge distance of the most distant fastener, psi.

d = depth of member, psi.

For a connection located a distance greater than or equal to five member depths

from the end of the member, allowable design shear is the following (AF&PA 2005):

evr bdFV ''

32

= (2-9)

In summary, for the design of perpendicular to grain connections, NDS

methodology consists of calculating the reference lateral design value (yield limit


equations) and additionally checking the shear stresses in the connection member

(allowable design shear check). ASD and LRFD calculate these values in different ways,

as will be discussed in the following sections. Principles of mechanics can be used to

transform the allowable design shear into a corresponding allowable connection

resistance. Therefore, the controlling connection design resistance is the smaller of

reference lateral design value and the connection resistance obtained from the allowable

design shear check. For clarity, this controlling connection design resistance will be

referred to in this research as the lateral design value (LDV).

2.2.3.1 Allowable Stress Design for Wood Connections

Allowable stress design, also referred to as factor-of-safety design, utilizes a

factor of safety, χ, to account for a number of unknowns. Typical unknowns are

‘variability of the loads, differences in material properties, deviations from the intended

geometry, and our ability to predict the critical parameter’ (Boresi and Schmidt, 2003).

For any given limit state, the ratio of the nominal resistance, R, to the factor of safety, χ,

must be greater than or equal to the sum of service loads, Q. In equation form, for N

number of loads, the inequality is the following (Boresi and Schmidt, 2003):

∑=

≤N

ii

RQ1 χ

(2-10)

Reference lateral design values are calculated for allowable stress design, by

determining the nominal lateral design value, Z, and ‘factoring’ it by “C” adjustment

factors (each denoted by a unique subscript). The NDS equation is as follows (AF&PA

2005):

Z’ = Z(CD)(CM)(Ct)(Cg)(CΔ)(Ceg)(Cdi)(Ctn) (2-11)

with,

Z = θnK

Pmin (2-12)

Where,

Z’ = reference lateral design value, lb.

Z = nominal lateral design value, lb.


Pmin = controlling value from NDS yield limit equations (or from the general dowel equations at the 5% offset yield limit state), lb.

n = adjustment factor

Kθ = angle of loading factor

CD= load duration factor (1.6 for connections with 10-minute load duration)

CM = wet service factor (1.0 for dowel connections with maximum of 19% moisture content during fabrication and in-service)

Ct = temperature factor (1.0 for connections with sustained temperatures below 150oF)

Cg = group action factor (applies for multi-fastener dowel connections with diameters less than 1 in., 1.0 for single fastener connections)

CΔ = geometry factor (1.0 for dowel connections satisfying spacing requirements)

Ceg = end grain factor (applies when dowels are ‘inserted in the end grain’, 1.0 otherwise)

Cdi = diaphragm factor (applies if dowels are part of a diaphragm system, 1.0 otherwise)

Ctn = toe-nail factor (applies if dowels are used in toe-nail connections, 1.0 for common bolt connection details)

The adjustment factor, n, is a function of yield mode for dowels greater than or

equal to 0.25 in. in diameter, and less than or equal to 1.00 in. in diameter. For double-

shear connections, the adjustment factor is 4.0 for modes Im and Is, and 3.2 for modes

IIIm, IIIs, and IV (AF&PA 2005).

The angle of loading factor, Kθ, which also applies to dowels greater than or equal

to 0.25 in. in diameter, and less than or equal to 1.00 in. in diameter, is determined by the

following equation (AF&PA 2005):

Kθ = 1 + 0.25(θ.90) (2-13)

Where: θ = angle of grain between load and grain directions

To determine the allowable design shear, the adjusted design shear parallel to

grain value, Fv’, is calculated from the tabulated design shear parallel to grain value of the

member, and multiplied by the applicable adjustment factors. These adjustment factors


are listed in Table 4.3.1, and described in Section 4.3, of the 2005 NDS. The formula to

calculate the adjusted design shear parallel to grain value is then (AF&PA 2005):

Fv’ = Fv(CD)(CM)(Ct)(Ci) (2-14)

where,

Fv’ = adjusted design shear parallel to grain value, psi.

Fv = tabulated shear parallel to grain value of the member, psi.

CD = load duration factor (same from Equation 2-11)

CM = wet service factor (same from Equation 2-11)

Ct = temperature factor (same from Equation 2-11)

Ci = incising factor (applies only for incised solid lumber, 1.0 otherwise)

Tabulated design shear parallel to grain values are given in the 2005 NDS for

sawn lumber, and listed in the manufacturers’ design literature for structural composite

lumber (AF&PA 2005).

Examples of allowable stress design value calculations can be found in Smart

(2002), Breyer et al. (2003) and in the 2005 NDS (AF&PA 2005).

2.2.3.2 Reliability-Based Design for Wood Connections

Reliability-based design differs from allowable stress design in that its

considerations extend to include statistical variations. Resistance is multiplied by a

resistance factor, Φ, which addresses variability ‘associated with material properties,

geometry, and analysis procedures’ (Boresi and Schmidt, 2003). Service loads, Q, are

multiplied by load factors, γ, which account for variability in loading. For any limit state,

the inequality representing this format for N number of loads, is as follows (Boresi and

Schmidt, 2003):

∑ (2-15) =

≤N

iii RQ

1φγ

Reference lateral design values are calculated for load and resistance factor

design, by determining the nominal lateral resistance, Z, and factoring it by several of the

same adjustment factors used by allowable stress design. Rheological considerations are


addressed by a time effect factor, λ. A resistance factor, Φ, is also applied. The NDS

equation for the LRFD reference lateral design values is as follows (AF&PA 2005):

Z’n = Zn(ΦZ)(λ)(CM)(Ct)(Cg)(CΔ) (2-16)

with,

Zn = Z(KF) (2-17)

Where,

Z’n = reference lateral design value, lb.

Zn = nominal lateral resistance, lb.

Z = nominal lateral design value (Equation 2-11), lb.

ΦZ = connection resistance factor = 0.65 for all fastener types

KF = format conversion factor = 2.16 / ΦZ = 3.32 for all fastener types

λ = time effect factor = 1.0 for 10-minute load duration

CM, Ct, Cg, CΔ = same adjustments as ASD (Equation 2-10)

From Equations 2-12 and 2-17, it should be noted that the difference between the

LRFD nominal lateral resistance, Zn, and the ASD nominal lateral design value, Z, is the

format conversion factor, KF. This conversion factor, which for connections is 3.32,

essentially serves as a ‘soft conversion’ from ASD to LRFD formats (AF&PA 2005).

In order to determine the allowable design shear, the adjusted LRFD shear value,

Fvn’ is calculated as a function of the adjusted design shear parallel to grain value, Fv.

The formula to calculate the nominal LRFD shear value is then (AF&PA 2005):

Fvn’ = Fvn(Φv)(λ)(CM)(Ct)(Ci) (2-18)

with,

Fvn = Fv(KF) (2-19)

Where,

Fvn’ = adjusted LRFD shear value (psi)

Fvn = nominal LRFD shear value (psi)

Fv = tabulated shear parallel to grain value (psi)

Φv = shear resistance factor = 0.75

KF = format conversion factor = 2.16/ Φv = 2.88 for shear


CM, Ct, Ci = same adjustments as ASD (Equation 2-13)

Again, it should be noted that the difference between LRFD and ASD shear

values is a ‘soft-conversion’ in the form of the format conversion factor, KF. For shear,

this conversion from ASD to LRFD is 2.88 (AF&PA 2005).

Examples of LRFD calculations can be found in the 2005 NDS (AF&PA 2005).

2.3 Fracture Mechanics-Based Models

Numerous researchers (specifically those referenced in Sections 2.3.1 and 2.3.2)

have found during experimental analysis of perpendicular to grain connections that

failure modes typically include splitting. Several researchers have applied principles of

fracture mechanics in attempts to predict the capacity resistance achieved before splitting

occurs, as fracture mechanics pertain especially to brittle failure modes such as splitting

(also referred to as cracking). Specifically, linear elastic fracture mechanics theory, and

additionally quasi-non-linear fracture mechanics theory, has been utilized to develop

relatively simple models.

The two most common approaches of linear elastic fracture mechanics (LEFM)

are the strain energy release rate method, and the stress intensity factor method. Strain

energy release rate methodology is based on the Griffith theory of system energy balance,

while the stress intensity factor methodology focuses on the distribution of local stresses

in close proximity of the crack tip (Smith et al. 2003). LEFM models based on either

approach, follow several fundamental assumptions. Fracture is hypothesized to occur

due to cracks created by propagation of a fracture process region, which is relatively

small in comparison to the dimensions of the member (Jensen 2003). Three possible

fracture modes (depicted. in Figure 2-2) are considered: Mode I Opening/Tension, Mode

II In-plane Shear, and Mode III Out-of-plane Shear. Mixed-mode combinations of the

three modes are also allowed. The material is also assumed to exhibit linear elastic

behavior to the point of fracture.

Models based on quasi-non-linear fracture mechanics account for the fracture

process region characteristics by introducing a deformation layer along the expected path

of crack propagations, based upon beam-on-elastic foundation (BEF) theory. This layer,


the foundation stiffness, is assigned properties that will accurately represent the fracture

energy and tensile strength of the wood material (Jensen 2003). As in LEFM, material

behavior is treated as linear elastic, but the tensile strength is assumed to be a finite value

instead of infinite as it is considered to be in LEFM. Another key difference of quasi-

non-linear fracture mechanics analysis is that the failure load and the square root of

fracture energy are not proportional, as is the case in LEFM (Jensen 2005). Considered

fracture modes are identical to those utilized by LEFM (Figure 2-2).

Mode I Mode II Mode III Opening/Tension In-plane Shear Out-of-plane Shear

Figure 2-2: Fracture Modes Considered by Linear Elastic Fracture Mechanics (after

Jorissen 1998)

2.3.1 Van der Put Model

The research of Van der Put (1990) presented a successful application of fracture

mechanics to notched beams. The same principles and the method of superposition

served as the basis of the Van der Put model. Several simplifying assumptions were also

used to develop the model. The presence of normal forces in the cross section of the

member at the location where stable splitting occurred, were neglected in the derivation.

Criteria for the initiation of crack propagation was defined as when the loss of potential


energy due to cracking, was equal to the required energy for crack formation. An

additional requirement was that the fracture energy, Gf, associated with crack

propagation, must be of sufficient magnitude to propagate the crack in both the length

and width directions of the beam. A final assumption required stable crack propagation

(Van der Put and Leijten 2000).

The relationship for splitting failure, derived in full in the work of Van der Put

and Leijten (2000), is the following:

( )αα−

=16.0f

f GGhb

V (2-20)

where,

α = he / h = location of the dowel with respect to the loaded edge and the beam height

b = beam width, mm. he = loaded edge distance, mm. h = beam height, mm. G = shear modulus of the material, N/mm2

= fracture energy, N/mm fG = the maximum shear force at fracture, N fV

The theoretical basis of the model has been questioned due to the neglection of

the normal forces at the cracked section of the beam, which is an incomplete static

representation of equilibrium at the section. Additional analysis including the normal

forces at the cracked section of the beam, has determined that these forces are a

negligible contribution to the model (Jensen 2003).

The fracture energy term, Gf, as referred to by Van der Put and Leijten (2000),

assumes a combined (mixed-mode) mode I and mode II interaction. This interaction was

derived empirically by Petersson (1995), based on the relationship between tension

perpendicular to grain stress and shear stress. However, a simplifying assumption of Gf

based only on mode I fracture, is a reasonably accurate approximation (Schoenmakers

2006).

An alternate form of Equation 2-20 is the following (Van der Put and Leijten

2000):


( )αα−

=11C

hbV f with

6.01fGG

C = (2-21)

The research of Ehlbeck et al. (1989) and Ballerini (1999), both of which

conducted connection tests of nails and dowels loaded perpendicular-to-grain in simply

supported beams, was successfully used to determine the apparent fracture parameter,

, through calibration (Van der Put and Leijten 2000). Successful calibration was also

achieved with the research of Reshke (1999) which tested simply supported and

cantilevered spruce glulam beams with steel-timber-steel bolted connections loaded

perpendicular-to-grain, and the research of Reffolds et al. (1999) which tested punched

metal plate connections loaded perpendicular-to-grain. This calibration determined the

C

1C

1 characteristic lower bound for loaded edge distance less than 70% of the depth of the

member, defined as 2/3 of the lower bound, to be 10 N/mm1.5 (Van der Put and Leijten

2000). Substitution of this value into equation 2-21, yields the following:

( )αα−

=1

10hb

V f (2-22)

The work of Snow et al. (2004b) analyzed the accuracy of the Van der Put model

in predicting the splitting capacity of perpendicular to grain, single-dowel connections in

laminated strand lumber (LSL). Comparisons between experimental results of

connections loaded to ultimate strength, and model predictions, concluded that model

predictions were relatively accurate. However, LSL connection members typically failed

in bending, rather than by splitting propagating from the connection. Additional work

from Snow et al. (2004a) extended experimental analysis of perpendicular to grain single-

dowel connections to include laminated veneer lumber (LVL) and parallel strand lumber

(PSL). Both materials exhibited splitting behavior at failure; analysis of the Van der Put

model was not included in the scope of the project. It should be noted that the

experimental connection configurations of Snow et al. (2004a) and Snow et al. (2004b)


both consisted of a 3/4 in. diameter dowel loading the main member, of 3-1/2 in. depth,

along the neutral axis. The loaded edge distance of this configuration, 2.33D, is

considered unsatisfactory by current NDS requirements of a minimum 4D loaded edge

distance for perpendicular to grain connections.

2.3.2 Jensen Model

The quasi-non-linear fracture mechanics model created by Jensen et al. (2003)

was based upon beam-on-elastic foundation (BEF) theory. A complete model derivation

using the conventional stress method, finite element solution, and experimental validation

was provided by Jensen et al. (2003). The model was based on an elastic Timoshenko

beam with finite length, with support provided by linear elastic springs connected to a

stiff foundation. The foundation stiffness of these springs modeled the perpendicular to

grain strength and fracture performance of the wood. While this performance is non-

linear, it is “represented by a linear response that is equivalent in terms of peak tensile

stress perpendicular to grain, , and fracture energy dissipations, ”. Failure criterion

for the beam was defined as when the maximum stress is equal to of the wood (Jensen

et al. 2003).

tf fG

tf

The model equations for failure load of a single dowel loading a beam

perpendicular to grain are as follows (Jensen et al. 2003):

efLEFMPp hGGbPP320

, μμ == (2-23)

with 112

++

=ςςμ and 2

2

35

te

f

fhEG

EG

=ς

where, b = beam width, mm. = distance from the closest dowel to the loaded edge, mm. eh G = shear modulus of the material, N/mm2

= fracture energy perpendicular to grain (mode I), N/mm fG E = modulus of elasticity of the material, N/mm2

= tensile strength perpependicular-to-grain, N/mmtf 2


= the failure load as a LEFM solution, N LEFMPP ,

= the failure load, N PP

Finite element model (FEM) analysis of a ‘symmetrical beam with one or more

dowels’ was performed by Jensen et al. (2003) in order to determine the accuracy of the

derivation based on BEF theory. Good correlation was shown between experimental

failure loads of laminated veneer lumber (LVL) plate and beam specimens, and

theoretical predictions. The theory was also applied to structural glued laminated timber

(glulam) beams with relatively low span to beam depth ratios, and plate tests, performed

by Yasumura (2001), Quenneville and Mohammad (2001), and Kasim and Quenneville

(2002). The glulam plates showed good agreement between theoretical predictions and

experimental results. The capacity of the glulam beams was shown to be over-predicted

for larger loaded edge distances (Jensen et al. 2003).

An alternate model derivation following the compliance method, and

experimental tests of Japanese cedar glulam plate joint specimens, determined that by

using a foundation stiffness that adequately represents the tensile strength and fracture

energy properties of the wood, the same failure load is predicted from either derivation

approach. Crack length variation was also shown to be accounted for in the model

(Jensen 2005).

The previously mentioned work of Snow et al. (2004b) also included analysis of

the accuracy of the Jensen model in predicting the splitting capacity of perpendicular to

grain, single-dowel connections in laminated strand lumber (LSL). As with the Van der

Put model, comparisons between experimental results of connection loaded to ultimate

strength, and model predictions, concluded that model predictions were relatively

accurate. However, again it should be noted that LSL connection members typically

failed in bending, rather than by splitting propagating from the connection.

2.3.3 Eurocode 5 (EC5) Splitting Capacity

A manifestation of Equation 2-22, appears in the European design code (Eurocode

5 or EC5) as a specific check of the splitting capacity for perpendicular-to-grain


connections in softwoods. The formulas, denoted as Equations 8.4 and 8.5 in Eurocode

5, are the following (ENV 2005-1-1, 2004):

⎟⎠

⎞⎜⎝

⎛ −=

hh

hbwF

e

eRk

114,90 (2-24)

with

⎪⎪

⎭

⎪⎪

⎬

⎫

⎪⎪

⎩

⎪⎪

⎨

⎧

⎪⎭

⎪⎬

⎫

⎪⎩

⎪⎨

⎧⎟⎟⎠

⎞⎜⎜⎝

⎛

=

11

100max

35.0plw

w For punched metal plate fasteners

For all other fasteners

where,

F90,Rk = the characteristic splitting capacity, N

w = modification factor for fastener type

he = loaded edge distance of the most distant fastener, mm

h = member height, mm

b = member width, mm

wpl = width of the punched metal plate fastener parallel to the grain, mm

Accounting for material type, load duration, and moisture content effects, the

following equation (Section 2.4.3 of Eurocode 5) relates the characteristic value to the

design value (ENV 2005-1-1, 2004):

M

RkRd

FkF

γ,90

mod,90 = (2-25)

Where,

F90,Rd = design splitting capacity, N

kmod = partial factor for material properties = 1.3 for connections

γM = modification factor considering load duration and service moisture content = 0.9 for solid wood/LVL under a short term load (less than one week) with moisture content not exceeding 20%


2.4 Current Reliability-Based Design State of the Art

Current U.S. connection design methodology was reviewed in Section 2.2.

Design formats include the option of design by either ASD or LRFD. While LRFD is

considered a reliability-based design format, the format as given by the NDS is still

largely-defined by a soft-conversion from ASD. The same method is utilized by LRFD

formats in place by Canadian, European, and Australian design codes (Smith and

Foliente, 2002). Thus, LRFD design for wood connections is not a purely reliability-

based design format. In contrast, LRFD formats for concrete and steel design are

completely reliability-based.

As summarized by Smart (2002) and Köhler et al. (2006), several factors

contribute to this delayed development for LRFD wood design. First, due to the

uniqueness of wood in term of its time-dependent mechanical properties, loading

considerations from concrete and steel models cannot be directly applied (Foschi et al.

1989). Second, mechanical properties of wood are highly variable, and are affected by

the hygroscopic and anisotropic nature of the material (Bodig and Jayne 1982). Finally,

performance factors cannot be accurately calibrated due to a lack of research

investigating connection resistance at capacity (Foschi et al. 1989).

Calibration of reliability-based parameters for structural members is currently

ahead of that for connections. An example of which is the work of Rosowsky et al.

(2005) which focused on calibration of reliability parameters for members under a

bending-load limit state (such as beams, joists, etc.). Similar work has not been

completed for connections; the behavior of which is significantly more complex and

difficult to characterize for the seemingly endless possible combinations of joint

configurations (Smith and Foliente 2002).

To make purely reliability-based parameters a possibility, progress must be made

towards the better understanding of connection performance at capacity resistance. The

work of Smart (2002) presented a specific investigation into the behavior of single-shear,

monotonically-loaded, nailed and bolted parallel to grain connections. Over-strength

values, a relation of capacity resistance to current LRFD predicted resistance, were

quantified for variables including dowel diameter, member species, and member

thickness. It should be noted that no research of similar scope, has been conducted for


perpendicular to grain connections. Bolted connections of this orientation, have been

specifically classified as a ‘high priority’ by Smith and Foliente (2002) for the

advancement of LRFD of connections.

2.5 Summary

Current American lateral connection design can be conducted by either ASD or

LRFD formats, both of which are based upon the yield model. Numerous studies have

been conducted investigating connection behavior and factors that affect embedment

resistance, a key input into the yield model. While LRFD is also utilized by Canada,

Europe, and Australia, in the design of laterally-loaded connections, several modeling

alternatives exist. In particular for perpendicular to grain connections, which tend to

exhibit splitting behavior, fracture mechanics-based models present a relatively simple

and user-friendly option for the prediction of connection capacity.

At present, LRFD as it appears in the American lateral-connection design code

(NDS), calculates values from ASD by means of a ‘soft conversion’. At present there

remains a lack of knowledge regarding the behavior of connections at capacity resistance.

Such knowledge, which has been labeled as a ‘high priority’ in particular for

perpendicular to grain bolted connections, is needed to calibrate LRFD parameters on a

pure reliability basis. This research will contribute to such knowledge.


Chapter 3: Materials and Methods

3.1 Introduction

The following sections detail all methods and materials used in conducting this

research. All specimen fabrication and testing was conducted at the Brooks Forest

Products Center of Virginia Polytechnic Institute and State University. The testing

program consisted of two major components: connection testing and material testing.

Material testing included Mode I fracture, modulus of elasticity, shear modulus, tension

perpendicular to grain strength, dowel embedment strength, bolt bending strength,

moisture content, and specific gravity tests.

With the exception of modulus of elasticity and shear modulus, all specimens for

the remaining material tests were cut from the connection specimens following

completion of the connection testing. Because of the elastic nature of the two modulus

tests, and as a material use efficiency consideration, a subset of samples used for the

connection tests specimens were first used for modulus of elasticity and shear modulus

testing. The succession of testing in the experimental design, is illustrated in Figure 3-1.

The details of the succession are elaborated upon further in Sections 3.4.2, 3.5.1 and

3.5.2.

Tensile Strength Perp-to-Grain (ft)

Fracture Energy (GIf)

Modulus of Elasticity (E)

Shear Modulus (G)

Connection Tests

Dowel Bearing Strength (Fe) MC and SG

Dowel Bending Strength (Fb)

Figure 3-1: Experimental Design Flow Chart – Succession of Testing


3.2 Materials

Three materials were used in the connection and material testing portions of this

research. These included machine stress-rated (MSR) lumber, laminated veneer lumber

(LVL), and parallel strand lumber (PSL). MSR lumber specimens were southern pine

(Pinus spp.), rated 2400f-2.0E, and were obtained as a donation from Timber Truss

Housing Systems, Inc of Salem, VA. LVL specimens were predominantly of southern

pine (Pinus spp.) parent material and rated 3100f-2.0E. While a majority of the LVL

veneers were southern pine, two sheets (or approximately 20% of the lay-up) were

eucalyptus (Eucalyptus spp.). PSL specimens were of Yellow-poplar (Liriodendron

tulipfera) parent material and rated 2900f-2.0E.

A nominal 2x8 (1.5 in. x 7.25 in.) cross section was chosen as the main member

in the connection test. MSR lumber material was received at these dimensions. Care was

taken to obtain LVL at the desired 1.5 in. thickness as opposed to the more readily

available 1.75 in. thickness, as the required planing of the latter would have removed

exterior full and partial veneers from the lay-up and presumably altered the mechanical

properties of the material from its originally manufactured properties. PSL lumber

material was received at its lowest manufactured thickness, 3.5 in. The desired thickness

was obtained by ripping the section in two and planing the thickness down to 1.5 in. This

was deemed acceptable because PSL is commonly ripped from a larger billet during

manufacture (Smulski 1997). Both LVL and PSL specimens were trimmed to the desired

depth with a table saw.

All bolts used in the connection tests were 1/2 in. diameter, low-carbon steel, SAE

J429 Grade 2 hex-head bolts. This specification of bolt has a rated minimum tensile yield

strength of 74,000 psi (Albright 2006). This diameter and specification of bolt were

considered to be an accurate representation of those typically used in ‘service’ timber

connections. In an effort to minimize potential for variation in strength, all bolts were

ordered together from the supplier, so that all bolts were from the same batch number and

from the same manufacturer.


3.3 Sample Size Determination

The sample size for the number of replications of each material was determined

from the following equation (Heine 2001):

2

222/ **2e

COVZn α= (3-1)

where: sample size =n

e = relative error (%) = Δ/mean

COV = coefficient of variance (unitless) = σ/mean

σ = standard deviation (same unit as mean)

mean = population mean (any unit)

Δ = absolute error (same unit as mean)

Zα/2 = area under the curve associated with a 100(1-α)% confidence

interval = 1.645 for a 90 percent level of confidence.

3.4 Connection Tests

3.4.1 Introduction

Connection testing followed the procedures outlined in ASTM D 5652-95,

Standard Test Methods for Bolted Connections in Wood and Wood-Based Composites

(ASTM 2005h), with the exception of several minor considerations described below. A

total of 120 connection specimens were tested, considering the variables of specimen

material (as described in Section 3.2), span:depth ratio of the specimen, and loaded edge

distance of the connection. Figure 3-2 provides a schematic of the span, depth, and

loaded edge distance, dimension variables. Connection testing consisted of monotonic

displacement-controlled compressive loading of a steel-wood-steel connection at midspan

of the simply supported main member of the connection, up to ultimate load.

The connection configuration was designed for a predicted mode Im yield limit

failure, as yielding of the steel side plates or bolt was outside of the scope of this

research. Preliminary TR-12 calculations (see Section 2.2.3) were performed for the


proposed connection configuration, to ensure that mode Im was the controlling failure

mechanism.

Load Unloaded Edge Distance

Span

Overall Length

Loaded Edge Distance

Depth

Figure 3-2: Schematic of Connection Specimen Dimensions

The range of span:depth ratios included in this research were 3:1 (the minimum

allowed according to ASTM testing protocol), 5:1, and 10:1 (ASTM 2005h). This

variable considered the effects of shear and flexure on perpendicular to grain

connections; with a span:depth ratio of 3 being controlled primarily by shear forces, and a

span:depth ratio of 10 representing a larger component of flexural forces. Larger

span:depth ratios were not considered for practicality considerations of specimen length.

In addition, a subset of continuously supported members (span:depth ratio of zero) was

also included. This served as a preliminary investigation of a connection mimicking the

typical residential deck-to-house connection detail of a continuously supported band joist

loaded by a deck ledger.

The range of loaded edge distances included in this research, represented as a

multiple of the fastener dowel diameter, were 4D (the minimum allowed by the NDS for

a perpendicular-to-grain loading bolt condition), 7D, and 10D (AF&PA 2005).

3.4.2 Specimen Preparation

For sample size determination, the coefficient of variance was taken to be 10%,

the maximum COV value found by Snow et al. (2004a) during testing of Pine, LVL, and

PSL beams loaded perpendicular to grain by a single dowel. According to Equation 3-1,

a sample size of six assured with 90 percent confidence that the estimated mean was


within 10 percent of the true mean. While ASTM D 5652 typically recommends a

minimum sample size of ten, the smaller sample size for this case was allowable because

of the coefficients of variation from prior testing with similar objectives (ASTM 2005h).

The sample size was increased to ten for the 10:1 span:depth ratio specimens, as these

specimens were also used in modulus of elasticity and shear modulus testing, which

required a minimum of ten samples. Table 3-1 provides a summary of replications for

each test configuration of the connection testing program.

Table 3-1: Test Configurations and Replications for Connection Testing

Span:Depth Ratio Bolt Diameter

Main Member Material

Loaded Edge Distance (xD) 0:1 3:1 5:1 10:1 Totals

4 3 6 6 10 25 7 3 6 9 PSL

10 6 6 4 3 6 6 10 25 7 3 6 9 LVL

10 6 6 4 3 6 6 10 25 7 3 6 9

1/2”

MSR 10 6 6

Totals 18 18 54 30 120

The length of specimens was determined by the specified span to depth ratio, with

an additional four inches on each end to provide sufficient bearing area at the supports.

While this length of bearing was considered to be sufficient to prevent substantial bearing

failure at the supports, support bearing crushing was measured separately during testing,

so it could be accounted for in the load-displacement data for the connection test.

Continuously supports specimens were cut to the same length as the 3:1 span:depth ratio

specimens. The corresponding lengths for each span to depth ratio, are listed in Table 3-

2, and illustrated above in Figure 3-2.


Table 3-2: Specimen Lengths for Varying Span:Depth Ratios

Span:Depth Ratio Span (in.) Overall

Length (in.) 0:1 0.00 29.75 3:1 21.75 29.75 5:1 36.25 44.25

10:1 72.50 80.50

Upon the acquisition of each material, specimens were cut according to the

appropriate lengths and quantities, shown in Table 3-1 and Table 3-2, for the connection

testing program, and placed in an environmental chamber for a minimum of 5 weeks (35

days). Chamber conditions were sustained at 65% ±1% relative humidity (RH) and 20OC

±1OC (68OF ±1.8OF). This conditioning period reduced the potential for moisture content

(MC) variability, by allowing the specimens to reach an equilibrium moisture content

(EMC). Moisture content samples were taken on weekly time intervals to verify that a

stable moisture content for each material had been obtained. Specimens were

conditioned for the duration of the testing program.

Upon conditioning, the 10:1 span:depth ratio specimens were subjected to testing

to determine the modulus of elasticity and shear modulus, and subsequently returned to

the environmental chamber until connection testing commenced.

Bolt holes in the specimens were drilled within one day of connection testing.

Holes were drilled using a drill press with a 9/16 inch spade drill bit, in order to provide

1/16 inch oversizing for the 1/2 inch bolts of the connection. Locations of bolt holes

were at the distance of the corresponding loaded edge distance of the member, which are

given in Table 3-3.

Table 3-3: Lengths of Varying Loaded Edge Distances

Loaded Edge Distance (Edge to Center of Hole)

Dowel Diameters (D) Distance (in.) 4 2.0 7 3.5

10 5.0


3.4.3 Specimen Identification

Due to the variables of consideration in the experimental program, a specimen

identification system was used in order to efficiently identify each specimen. This

system consisted of a set of four identifiers. The first identifier classified the material

type, where “P” represented PSL, “L” represented LVL, and “M” represented MSR

lumber. The second identifier denoted the clear span:depth ratio of the main member of

the connection test. The third identifier was the connection loaded edge distance of the

member, as a multiple of the bolt diameter (D), in inches. The fourth identifier was the

specimen number within its sample set.

The following is an example of this system:

P-5-7-2

This example represented a PSL specimen with a span:depth ratio of 5:1 and a

connection loaded edge distance of 7D. The specimen was the second of its sample set.

3.4.4 Connection Layout

Figure 3-3 shows a schematic of the connection layout and fixture. The double-

shear connection layout was located at midspan of the simply supported main member,

with the connection fixture consisting of two steel side plates, connected to a bearing

plate at the top. The fixture was loaded in compression by the load head of the MTS

machine bearing on the fixture bearing plate.


Span/2 Span/2

Steel Side Plate

Bearing Plate

MTS Load Head

Support bearing plate Bolt

Figure 3-3: Connection Layout Diagram

The side plates of the connection fixture were manufactured from 1/2 in. thick

A36 steel, with length 7 in. and width 3 in. Oversized holes (5/8 in.) were drilled an inch

in from each end, along the centerline of the width axis, to accommodate the connection

bolts. While only one hole was in used during each connection tests, two holes were

drilled so that the side plates could be reversed if significant bearing deformation

occurred around the original hole during the testing program. The side plate

configuration is shown in Figure 3-4. Both ends of the side plates were tapped with

threaded holes, as part of the connection to the bearing plate.


5”

1”

1”

1-1/2” 1-1/2”

5/8”

Tapped Holes

Tapped Holes

Figure 3-4: Connection Fixture Side Plates

The bearing plate of the connection fixture was manufactured from 1 in. thick

A36 steel, with length 6 in. and width 3 in. In order to provide a rigid connection to the

side plates, the bearing plate was slotted along its length, in order for screws to be

inserted flush with the bearing surface of the plate. These screws then were threaded into

the tapped holes in the ends of the side plates. The versatility of this connection detail

allowed for the position of the side plates to be adjusted laterally to snugly fit the main

member of the connection, which prohibited the opportunity for a gap to be present in the

connection. Details of this fixture connection are shown in Figure 3-5.


(a) (b)

Figure 3-5: Connection Fixture – (a) Side View – (b) Top View

Installation of the connection fixture involved placing the 1/2 in. bolt for each

connection test, through the predrilled main member and side plates. Washers and a 1/2

in. nut were then turned finger tight on the bolt. The fixture was maintained in a vertical

position then by the tension of the bolt.

3.4.5 Connection Testing Procedure

Figure 3-6 shows the test setup used for all connection evaluation. Lateral

support was provided at third points of the span of the connection test specimen to

adequately brace the member against buckling. Lateral supports were covered with a

layer of high density polyethylene (HDPE) to minimize frictional effects (Harrison 2006).


Supports

Lateral Supports

Figure 3-6: Simply Supported Connection Specimen with Lateral Supports

The testing apparatus consisted of a 55,000 lb. capacity MTS universal testing

machine, outfitted with a 20,000 lb. capacity load cell attached to the load head. A series

of linear variable differential transformers (LVDT’s), as described below, were used to

record deflection measurements. Electronic measurements from the load cell, and LVDT

were processed through LabVIEWTM 7 Express data acquisition software.

Prior to the actual connection test loading, the connection test specimen was

loaded to 100 lbs. to remove slack from the system by seating the bolt in the connection

and at the supports. This load was then removed, and the connection test loading was

initiated. Displacement controlled load was applied at a rate of 0.035 in./min, until

capacity (maximum) load was obtained. Maximum load was considered to have been

achieved whenever the load level dropped by 10% of the maximum value, with no

indication of recovery. This rate of loading followed the ASTM recommendations of

arrival at maximum load in 5 to 20 minutes (ASTM 2005h).

For displacement measurement, the measurement arrangement of Reshke (1999)

was utilized in lieu of the ASTM D 5652 LVDT configuration, as it allowed for joint slip

measurements to be separated into wood splitting and wood bearing failure components.

Instrumentation included a total of six LVDT’s and string potentiometers, each placed at


different locations on the connection test specimen. For consistency of labeling, these

instruments were labeled as LVDT 1 to 6. A general description of the configuration is

summarized in Table 3-4. A diagram of the configuration is shown in Figure 3-7.

Table 3-4: LVDT Descriptions and Locations

LVDT Label Number Measurement Description/Location 1 Left support displacement 2 Right support displacement 3 Fixture displacement – back side plate 4 Fixture displacement - front side plate 5 Displacement of top edge of specimen 6 Displacement of bottom edge of specimen

LVDT 1 LVDT 2

LVDT 6

LVDT 5

LVDT 4

LVDT 4 LVDT 3

Figure 3-7: LVDT Configuration Diagram

LVDT 1 and LVDT 2 (2 in. range, 0.001 in. sensitivity) measured support

deformation of the main member of the connection, with respect to the base of the testing

machine. The LVDTs were mounted to the testing machine base on each end. LVDT

cores were hung from brackets mounted on the connection test member, two inches from

the bottom of the member along the center of bearing (see Figure 3-8).


Bracket

Support

LVDT

Figure 3-8: LVDT 1 and 2 Installation Detail

LVDT 3 and LVDT 4, both string potentiometers, (5 in. range, 0.012 in.

sensitivity) measured displacement of the connection fixture with respect to the MTS

load head. These were mounted on the base of the testing machine on both sides of the

fixture, and connected to the side plates of the fixture with a rod threaded into the fixture

itself (Figure 3-9). The rod/fixture connection was tightened with the use of a nut, in

order to prevent movement of the rod during testing.


String Potentiometer

Connecting Rod

Figure 3-9: LVDT 3 and 4 Installation Detail

LVDT 5 (2 in. range, 0.001 in. sensitivity) measured displacement of the top edge

of the connection test specimen. This gaging LVDT was mounted to a fixture which

extended above the test specimen from the base of the testing machine, and touched a

bracket mounted on the center of the connection test specimen (Figure 3-10).

BracketLVDT

Figure 3-10: LVDT 5 Installation Detail


LVDT 6 (1.5 in. range, 0.001 in. sensitivity) measured displacement of the bottom

edge (tension face) of the connection test specimen. It was mounted from the base of the

testing machine. The core was suspended from a bracket mounted on the bottom edge of

the connection test specimen (Figure 3-11). The bracket was attached with a quick-

setting epoxy, as a screw would have significantly reduced the member cross section at

this critical location.

LVDT

Bracket

Figure 3-11: LVDT 6 Installation Detail

From the configuration of LVDT’s listed above, joint performance characteristics

were calculated by the following expressions (Reshke 1999):

Fixture displacement = (LVDT 3 + LVDT 4) / 2 (3-2)

Support displacement = (LVDT 1 + LVDT 2) / 2 (3-3)

Joint cracking = LVDT 6 – LVDT 5 (3-4)

Joint bearing = Fixture displacement – LVDT 6 (3-5)

Joint slip = Joint cracking + Joint bearing (3-6)

Flexural displacement = LVDT 6 – Support displacement (3-7)


Fixture displacement represented the average of the two displacement readings

taken from the sideplates of the connection fixture. Support displacement represented

bearing failure at the supports of the connection specimen. Joint cracking measured the

amount of splitting present in the main member of the connection, by computing the

difference between the displacements of the bottom and top edge of the connection test

specimen. Joint bearing measured the amount of deformation due to the dowel bearing

on the main member, by the difference between the fixture displacement and the bottom

edge of the connection specimen. Joint slip was the sum of the joint cracking and joint

bearing components. Flexural displacement represented the deformation of the bottom

edge of the connection specimen, without the effect of support crushing.

With these parameters, plots of load vs. joint slip were obtained for each test.

Subsequent analysis included determination of the 5% offset yield load and the ultimate

(capacity) load, and the corresponding displacements.

At the completion of each connection test, the mode of failure was also noted by

visual inspection. Lengths of any noticeable cracks were also recorded. Finally, the

vicinity of the bolt hole in the main member was preserved in case of any need for future

analysis. This was done by making two table saw cuts three inches off of the center of

the connection, yielding a six inch long, full-depth, full-thickness block, with the

connection centered length-wise.

3.5 Material Tests

Material testing included Mode I fracture, modulus of elasticity, shear modulus,

tension perpendicular-to-grain, dowel embedment strength, bolt bending strength,

moisture content, and specific gravity tests to provide accurate values for the inputs of the

TR-12 and fracture model equations.

Values of shear modulus for design purposes are usually approximated by relation

to the modulus of elasticity by an assumed E:G ratio of 16:1 (Bodig and Jayne 1982).

This practice typically is conservative, as torsional rigidity is rarely the controlling

variable for wood or SCL members in light frame construction. However, a sensitivity

analysis of the fracture model equations with the range of E:G ratios found in the

experimental results of Harrison (2006), and the normal E:G ratio assumption of 16:1,


showed percentages of error greater than 25% between actual and assumed values.

Therefore, direct measurement of shear moduli was determined to be an essential element

of this experimental program.

A summary of the succession of material tests conducted is given in Figure 3-1.

Dowel embedment, tension perpendicular to grain, Mode I fracture, and moisture content

and specific gravity specimens, along with the aforementioned center block, were

subsequently cut from tested connection specimens. The material test specimens were

cut from undamaged portions, as close to the center block as possible. Because of the

common occurrence of splitting, depending on the loaded edge distance, specimens had

to be cut either above or below the splitting. A typical example of the locations for

removal of material test specimens, from a tested connection specimen, is presented in

Figure 3-12.

Splitting ab

c de

Connection specimen

Figure 3-12: Typical Locations of Specimens Removed from a Tested Connection Specimen – a.) Center Block, b.) Dowel Embedment Specimen, c.) Tension Perpendicular to Grain

Specimen, d.) Mode I Fracture Specimen, e.) Moisture Content and Specific Gravity Specimen

3.5.1 Shear Modulus Tests

Shear modulus was measured using the torsion test outlined by ASTM D 198-05,

Standard Test Methods of Static Tests of Lumber in Structural Sizes (ASTM 2005b).

Research by (Harrison 2006) showed that the torsion test was a suitable method for

accurate measurement of the shear modulus of wood composites. This method consisted

of a specimen being fixed at one end while a torque was applied to the opposite end.

Troptometers were fastened at symmetric points along the length of the specimen, for

measurement of angular deflection. The apparent shear modulus of the material was then


determined from a relationship between parameters including the specimen dimensions,

proportional limit values of torque and angle of twist, and a Saint-Venant’s constant

given by ASTM D 198 (Harrison 2006).

For sample size determination, the coefficient of variance was taken to be 7.5%,

the maximum COV value found by Harrison (2006) during testing of MSR lumber and

LVL. Thus according to Equation 3-1, a sample size of ten assured with 90 percent

confidence that the estimated mean was within 5.5 percent of the true mean.

Due to the specimen length requirement being a minimum of eight times its

largest cross-sectional dimension, and in an effort to efficiently use material, the un-

drilled 10:1 span:depth length connection test specimens, which were also used in

modulus of elasticity testing, were used as the shear modulus test specimens. Similar

procedures of repeated measures type protocols for multiple test evaluations of the same

specimen group were used by Janowiak et al. (2001) and Harrison (2006).

Testing apparatus consisted of a MTS universal testing machine torsion actuator

with a 50,000 in.-lb capacity, and a fixed end grip, as shown in Figure 3-13. Both

elements were bolted to the laboratory floor to provide a rigid connection. Specimens

were tested at a gage length, defined as the distance between the edge of the actuator grip

to the edge of the fixed end grip, of 64 inches.

Figure 3-13: ASTM D 198 Torsion Test Setup with Specimen (after Harrison 2006)


Angular deflection measurements used two Accustar® II/DAS 20 Dual Axis

Clinometers (20 degrees rotation range, ±0.01 degrees sensitivity). Clinometers were

placed 16 in. from each end according to ASTM D 198 provisions (ASTM 2005b). The

gage length between the clinometers was 32 inches. Electronic measurements from the

torsion actuator, and clinometers were processed through LabVIEWTM 7 Express data

acquisition software.

Because the specimens would be used in the subsequent connection testing,

torsional loading rates and deflection limits were specified to ensure that test specimens

were loaded within the elastic range. Previous research by Harrison (2006) found that a

torsion loading rate of 3.5 degrees per minute, up to an angular deflection limit of seven

degrees, remains in the elastic range for 12 foot long wood members with a nominal 2x8

(1.5 in. x 7.25 in.) section. For the shorter length, deeper section members of this

research, a torsional loading rate of 0.5 degrees per minute, up to an angular deflection

limit of two degrees, was found by preliminary testing to be appropriate for elastic

loading.

Three repetitions of each specimen were tested. The apparent shear modulus was

then calculated with the average slope of the torque-angular displacement curve, by the

following equation (ASTM 2005b):

( )[ ] ⎥⎦⎤

⎢⎣⎡

−=

θλT

bhbhLG

)/(3/1616

3 (3-8)

where,

G = shear modulus (psi)

L = member gage length (in.)

b = width of member (in.)

h = height of member (in.)

λ = St. Venant constant

T/θ = slope from torque-angle curve (lb-in/rad).

3.5.2 Modulus of Elasticity Tests

The measurement of modulus of elasticity for each material followed the

procedures of the flexure test outlined by ASTM D 198-05, Standard Test Methods of


Static Tests of Lumber in Structural Sizes (ASTM 2005b). This method consisted of a

simply supported specimen loaded at midspan, with deflection measured at midspan.

For sample size determination, the coefficient of variance was taken to be 12.9%,

the maximum COV value found by previous research of Southern Pine lumber, LVL, and

PSL (Green and Kretschmann 1994) and (Janowiak et al. 2001). According to Equation

3-1, a sample size of ten assured with 90 percent confidence level that the estimated mean

was within 10 percent of the true mean.

The testing apparatus consisted of a 55,000 lb. capacity MTS universal testing

machine, outfitted with a 5,000 lb. capacity load cell attached to the load head. A yoke

deflectometer was used to measure deflection at the center of the beam with respect to the

neutral axis (ASTM 2005b). The yoke was suspended by two screws placed above each

support at the neutral axis of the beam. A LVDT was attached to the yoke at midspan,

while the metal core was suspended from the neutral axis of the beam at midspan. Data

from the load cell and LVDT were processed with LabVIEWTM 7 Express data

acquisition software. This loading configuration is shown in Figure 3-14.

Figure 3-14: Three-Point Bending Test Configuration (Harrison 2006)

In an effort to efficiently use material, the undrilled 10:1 span:depth length (80.5

in.) connection test specimens were used as the modulus of elasticity test specimens.


Clear span between supports was 72 inches. This length satisfied ASTM D 198

requirements for ‘beams intended primarily for evaluation of flexural properties’ having a

span:depth ratio between five and twelve. (ASTM 2005b). ASTM D 198 loading

considerations, specifically loading to capacity of the specimen, were not followed, as the

specimens would be used in subsequent shear modulus and connection testing. Loading

limits ensured specimens were stressed up to 60% of the allowable flexure stress of the

weakest material (fb = 2400 psi for the MSR). This stress corresponds to a maximum

load of 1500 lbs. for the specified member/loading configuration and load duration

(AF&PA 2005). Specimens were loaded at a rate of 0.20 in/minute up to a maximum

load of 1500 lbs.

Three repetitions of the loading were used. The average apparent modulus of

elasticity was calculated for each specimen according to Equation 3-9.

⎟⎠⎞

⎜⎝⎛Δ

=P

ILE f 48

3

(3-9)

where,

Ef = apparent modulus of elasticity (psi)

L = span (in.)

I = moment of inertia (in.4)

P/∆ = slope of load-deflection data (lb/in.).

To obtain the true material modulus of elasticity, the following equation given by

ASTM D 198 and utilized by Harrison (2006), was used:

2)/(111 LhKGEE f

+= (3-10)

where,

Ef = apparent material modulus of elasticity (psi)

E = true material modulus of elasticity (psi)

K = shape factor (5/6 for rectangular beams) (Harrison 2006)

G = shear modulus (psi)

h = height of beam (in.)

L = length of beam (in.).


Average shear modulus values were determined from the torsion test method

described in Section 3.5.1, and used to calculate the average true modulus of elasticity.

3.5.3 Dowel Embedment Tests

The measurement of dowel embedment strength followed the procedures of

ASTM D 5764-97a, Standard Test Method for Evaluating Dowel Bearing Strength of

Wood and Wood-based Products (ASTM 2005i). Because the half-hole test

configuration has been shown to cause premature failure for engineered wood product

materials, the full-hole test configuration was used (Carstens 1998). Specimens were cut

from members subjected to connection testing, from a location as close to the bolt

location as possible that remained undamaged from crushing or splitting (Figure 3-12).

Specimen dimensions were 2.5-in. wide, 1.5-in. thick, and 4-in. long, as depicted in

Figure 3-15. These specimen dimensions satisfied the recommendations given by section

8.2 of ASTM D 5764-97a, and were similar to the dimensions used by Carstens (1998),

who used specimens that measured 2.25-in. wide, 1.5-in. thick, and 4.25-in. long.

Once cut to the desired dimensions, each specimen was predrilled with a 9/16-in.

diameter hole in the center of its wide face. This corresponded to an oversizing of 1/16-

in. for the 1/2-in. diameter bolts used, which was the specified installation detail for bolts

given by the NDS (Breyer et al. 2003). This matched the bolt hole oversizing used in the

connection tests.


Figure 3-15: ASTM D 5764-97a Full-Hole Dowel Embedment Strength Specimen

The maximum coefficient of variation of 21.4% for dowel embedment strength at

5% offset and ultimate, reported by Carstens (1998) who tested both solid lumber and

LVL under the full-hole configuration, was used in evaluating the confidence level

associated with the chosen sample size. According to Equation 3-1, a sample size of 40

(one specimen cut from each connection test specimen) assured with 90 percent

confidence that the estimated mean was within 8 percent of the true mean.

The specimens were placed in the fixture shown in Figure 3-16, which consisted

of a bolt through the specimen and rigid steel side plates. The bolt used was a 1/2-in.

diameter high strength SAE J429 grade 9 bolt, in order to ensure the specimen failure

without any occurrence of bolt bending. A compression load was then applied to the end

of the specimen by a MTS testing machine with a floating load head that adjusted for any

eccentricities on the face of the specimen. The MTS machine used a 10,000 pound load

cell. A loading rate of 0.06 in./min, similar to that used by Carstens (1998), was used to

ensure a failure occurring between 1 and 10 minutes, as required by rate of testing

requirements given by Section 10.4 of ASTM D 5764-97a (ASTM 2005i).


Figure 3-16: ASTM D 5764-97a Dowel Embedment Test Setup

Interpretation of results followed Section 11 of ASTM D 5764-97a (ASTM

2005i). Dowel embedment strength values were determined by dividing the resistance

load by the bolt diameter and embedment specimen bearing length. Values were

calculated at both 5% offset yield and capacity. The 5% offset yield value was compared

to the predicted values calculated from the NDS dowel embedment strength equation

(Equation 2-3). For LVL and PSL, the equivalent specific gravity for fastener design

purposes was used to calculate the predicted values.

3.5.4 Bolt Bending Strength Tests

Because no standard exists for determining bolt bending strength, the procedure

of ASTM F 1575-03, Standard Test Method for Determining Bending Yield Moment of

Nails, was followed (ASTM 2005d). This was allowable according to NDS Section

11.3.5, which states that dowel bending strengths “shall be based on yield strength

derived using methods provided in ASTM F 1575 or the tensile yield strength derived

using procedures of ASTM F 606” (AF&PA 2005). The recommended procedure given

by ASTM F 1575 was for the fastener to be loaded in a three-point bending


configuration, with a span length defined as a function of the diameter of the fastener.

Specifically for the 0.5 in. bolts used in the connection testing of this research, the

required span length was 5.8 in. according to Table 1 of ASTM F 1575 (ASTM 2005d).

Because this span length was larger than the length of the bolts used during connection

testing, an alternate testing procedure was applied.

The cantilever bending test method used procedures similar to those employed by

Billings (2004) and Albright (2006). Relatively good correlation was found between the

three-point bending and cantilever bending configurations for 0.5 in. bolts, in the research

of Albright (2006). The method, as illustrated in Figure 3-17, consisted of a cantilevered

bolt threaded into a rigid support fixture, with a concentrated load applied a distance (x)

from the support fixture face. The bolt threads were excluded by being completely

covered by the support fixture.

Figure 3-17: Cantilever Bending Test Method Schematic (after Albright 2006)

A sample size of ten bolts was used, as it was determined by Albright (2006) to

ensure with 90 percent confidence that the estimated mean was within 10 percent of the

true mean. The distance (x) from the face of support to the location of load application,

was 2.5 in. for all specimens. The loading head used a cylindrical load point of 0.375 in.

diameter. Load was applied with a MTS universal testing machine at a rate 0.1 in./min,

using a 10,000 pound load cell. This test setup is shown below in Figure 3-18.


Figure 3-18: Bolt Bending Test Setup

From the recorded load displacement data of each specimen, the 5% offset yield

and capacity resistance values were calculated. According to Section 10.1 of ASTM F

1575, the 5% offset yield was determined by ‘fitting a straight line to the initial portion of

the load-deformation curve, offsetting this line by a deformation equal to 5% of the

[fastener] diameter, and selecting the load at which the offset line intersects the load-

deformation curve. In those cases where the offset line does not intersect the load

deformation curve, the maximum load shall be used as the yield load’ (ASTM 2005d).

Capacity resistance was defined as the maximum resistance from the load displacement

data of the specimen. For each of these values the bending yield strength, Fyb, was

calculated by the following equation:

ZMFyb = (3-11)

where,

Z = fastener plastic section modulus = D3/6 (in.3)

D = fastener diameter (in.)

M = applied moment = P*x (lb-in.)

P = 5% offset yield or capacity load (lb)


x = distance from face of support to the location of load application (in.).

The average bending yield strength, at 5% offset yield and capacity, of the ten

specimens was used as the value for the bolt material in yield model calculations.

3.5.5 Tension Perpendicular to Grain Tests

Samples for tension perpendicular to grain measurement were cut from members

after connection testing, from a location as close to the bolt location as possible that

remained undamaged from crushing or cracking (Figure 3-12). Procedures in accordance

with ASTM D 143-94 (ASTM 2005a) were followed for determination of the tension

perpendicular to grain strength. Although the common test specimen size was specified

to be 2-1/2 in. x 2 in. x 2 in., the specimen size tested was 2-1/2 in. x 2 in. x 1-1/2 in., as

shown in Figure 3-19, due to width considerations of the material.

The average coefficient of variation of 32.8% for tensile strength perpendicular to

grain was the maximum value reported by Hummer et al. (2006), was used in evaluating

the confidence associated with the chosen sample size. According to Equation 3-1, a

sample size of 40 (one specimen cut from each connection test specimen) assured with 90

percent confidence that the estimated mean was within 12 percent of the true mean.

Speed of testing was 0.10 in./min, as outlined by the ASTM standard, until the

ultimate load was reached (ASTM 2005a) The test fixture is shown in Figure 3-19.


Figure 3-19: ASTM D 193 Tension Perpendicular to Grain Specimen and Test Setup

Data recorded for each test specimen included a sketch of the fracture profile, and

the load-displacement curve from the test. The ultimate tension perpendicular to grain

stress was determined from analysis of the load-displacement curve, according to the

following equation:

A

Pf t

max= (3-12)

where,

tf = tension perpendicular to grain strength (psi)

Pmax = maximum load from load-displacement curve (lbs)

A = failure cross sectional area of specimen (in2)

3.5.6 Mode I Fracture Tests

At the time of this research there was not an established standard for the fracture

testing of wood. Development of testing procedures followed the work of previous

researchers investigating wood fracture, and existing fracture test standards for metals

and plastics. These standards were ASTM D 5045-99, Standard Test Methods for Plane-

Strain Fracture Toughness and Strain Energy Release Rate of Plastic Materials (ASTM


2005g), and ASTM E 399-90, Standard Test Method for Plane-Strain Fracture Toughness

of Metallic Materials (ASTM 2005c). These standards determine fracture energy through

integration of the load-displacement diagram obtained from fracture testing. Their

guidelines were not followed exclusively though, as they pertain to steel or plastic, which

are relatively homogeneous, isotropic materials, where wood is a non-homogeneous,

anisotropic material.

From the resources mentioned above, the following considerations were deemed

essential for inclusion in the experimental design:

1. The test apparatus consisted of the specimen held by a clevis, loaded in tension by

pins that allow for rotation of the specimen during testing. A constant

displacement loading rate was used, measured by the internal displacement

transducer of the testing machine. The load rate was such that minimal fast crack

propagation occurred, in order to produce a smooth load-displacement curve

(Ramskill 2002).

2. This configuration required the load-displacement curve to be corrected for

embedment effects due to the loading pins, which was accomplished by

performing indentation tests on un-cracked calibration specimens in accordance

with Section 9.2 of ASTM D 5045 (ASTM 2005g).

3. To minimize ‘size effects’ of the material and meet general linear elastic

conditions, the size of the crack surface created during fracture testing must be

large in comparison with the plastic zone located at the crack tip (the “fracture

process zone”) (Smith et al. 2003). A minimum ligament length (W-a) of 2.75

in., and minimum specimen width of 1.0 in., have been previously identified to

negate these size effects (Stanzl-Tschegg et al. 1995).

4. At least three replicates were recommended for each material considered (ASTM

2005g).

A significant modification from the procedures given by the ASTM standards,

however, was the omission of the requirement of plane strain at the crack tip. The criteria

given by ASTM D 5045, that Pmax/Pq ≤ 1.10, was not considered as this criteria is based

upon a metal material (Petterson et al. 1981). This was allowable because the mode I

fracture energy term, GIf, was determined by integration of the load-displacement curve,


as opposed to using the plane strain equation given in Section 9.3 of ASTM D 5045,

where GIf can be calculated as a function of the fracture toughness, KIc, and the modulus

of elasticity, E (ASTM 2005g). As a consequence of this approach, the fracture energy

measured in this research cannot be used to accurately calculate fracture toughness values

according to the assumption of a state of plane strain, as this assumption has not been

validated.

The type of specimen chosen was a compact tension (CT) specimen similar to that

successfully used by Ramskill (2002) in previous fracture testing of two species of solid-

sawn wood. Dimensions of a typical specimen are shown in Figure 3-20 (total length =

5.78 in., a = 1.75 in. (length of crack from center of dowel holes to end of crack), W =

5.39 in. (length of specimen from center of dowel holes to unslotted end), B = 1.5 in., h =

1.5 in., distance between center of dowels = 0.65 in., crack width = 0.12 in.) All cuts

were made with a table saw. A side view of the typical fracture specimen is shown in

Figure 3-21.

Figure 3-20: Fracture Specimen Dimensions (LVL Cross Section Shown)

(after Ramskill 2002)


Figure 3-21: Typical Fracture Specimen

Test apparatus included a MTS machine with a 10,000 lb. load cell., with

displacement measured by the internal transducer of the machine. The specimen was

loaded with two clevises, by 0.25 in. diameter loading pins running through the dowel

holes on each side of the notch. This configuration is shown in Figure 3-22.

Figure 3-22: Fracture Test Fixture (Shown with PSL Specimen)

Preliminary testing, involving a minimum of five replications for each material,

was used to measure the associated coefficient of variation (COV) for fracture energy.

Results found the highest coefficient of variation (COV) in fracture energy to be 25.5%,

for LVL. According to Equation 3-1, a sample size of 40 (one specimen cut from each


connection test specimen) assured with 90 percent confidence that the estimated mean

was within 10 percent of the true mean.

A loading rate of 0.075 in./min was also established from preliminary testing,

which typically produced fracture of the specimens in six to nine minutes. Tests were

concluded when recorded resistances decreased by 95% of the maximum load. From the

load-displacement curve, mode I fracture energy, GIf, was calculated by the following

equation (Smith et al. 2003):

A

WGIf = (3-13)

Where,

GIf = mode I fracture energy (lb-in/in2)

W = area under load-displacement curve (lb-in)

A = area of total crack propagation (in2)

3.5.7 Moisture Content and Specific Gravity Tests

Samples for moisture content and specific gravity measurement were taken

immediately after connection specimens were tested. Procedures in accordance with

ASTM D 4442-92, Method A (ASTM 2005f) were followed for determination of

moisture content. Following measurement of moisture content, the same specimens were

used with procedures in outlined by ASTM D 2395-93, Method B, Mode II (ASTM

2005e) for determination of specific gravity.

3.6 Property Definitions

The experimentally determined material properties and the experimental

connection geometries, mentioned above, were inserted as inputs into the TR-12 and

fracture model equations. The following values were calculated from connection test

data: 5% offset yield resistance, capacity (maximum) resistance, elastic stiffness, and

ductility ratio value. A representative load-slip curve is depicted in Figure 3-23, to aid in

the description of these values.


0.0

1000.0

2000.0

3000.0

4000.0

5000.0

0.0000 0.2000 0.4000

Displacement (Slip)

Res

ista

nce

(Loa

d)

0.05*D

5% Offset Yield

Capacity

Failure Elastic Stiffness

Figure 3-23: Representative Load-Slip Curve, with Calculated Values (after Smart 2002)

Elastic stiffness was defined as the slope of a line fit to the initial linear portion of

the load-slip curve. In order to determine 5% offset yield, the same line used to

determine elastic stiffness, was shifted to the right a distance of 5% of the dowel

diameter. 5% offset yield resistance and slip were then defined from the intersection of

the offset line and the load-slip curve. It should be noted that in cases where the

intersection point was located at a point beyond capacity, the 5% offset yield point was

considered to be equal to the capacity point.

Capacity was defined as the maximum resistance recorded by the load-slip curve.

Corresponding slip values were also calculated. In continuously supported cases,

resistance increased steadily throughout the duration of the test. Therefore in such cases,

a slip limit of 0.75 in. was used to define capacity if it had not been achieved prior in the

test. The magnitude of the slip limit was chosen to match that used during dowel

embedment testing.

While not considered in the analysis of this research, failure resistances and slips

were also calculated. Failure was calculated as either a 10% reduction from capacity

resistance, or a decrease in resistance with no sign of recovery. It should be noted that

this definition of failure deviated from that of previous researchers of parallel to grain


connections (Albright 2006, Billings 2004, Smart 2002), all of which defined failure as

20% reduction from connection capacity or a significant decrease in resistance with no

sign of recovery. This difference in definition was made under the consideration that

concluding the test just after the achievement of capacity, would provide for the

reasonable assumption that observed damage and failure modes were also those present at

capacity.

Ductility ratio was calculated from connection load-slip data. Specifically,

ductility ratio was calculated as the slip at capacity, divided by the slip at 5% offset yield.

This definition of ductility ratio was a slight variation of that used by previous

researchers of parallel to grain connections (Albright 2006, Billings 2004, Smart 2002),

who defined it as the slip at failure divided by the slip at 5% offset yield. This deviation

was made in consideration to behavior observed during connection testing of preliminary

specimens; in certain cases specimens split catastrophically at failure. With this trend of

a sudden sharp increase in connection slip, large amounts of variation were observed

when comparing failure displacements. Therefore, slip at capacity was substituted in

order to provide a more stable calculation of the parameter. As mentioned by Smart

(2002), given that ductility ratio is a ‘comparative value’ used to contrast ductility

between connection configurations, the difference in definition used by this research must

be noted.

Finally, average load-slip curves were constructed for each connection

configuration set. The protocol of Smart (2002), which consisted of plotting the average

curve to the extent of where slip values were available from every individual curve of the

set, was utilized to construct each average load-slip curve.


Chapter 4: Results and Discussion

4.1 General

This chapter contains the results obtained from experimental methods described in

Chapter 3, along with associated discussion. All connection test results are discussed in

Section 4.2. Material property test results are discussed in Section 4.3. Results

pertaining to the TR-12 model are discussed in Section 4.4, while Van der Put and Jensen

fracture model results are discussed in Section 4.5. Finally, discussion comparing the

TR-12 model, Van der Put model, and Jensen model, is included in Section 4.6.

Throughout this chapter and in associated appendices, the specimen identification

system described in Section 3.4.3 has been applied. References made with the fourth

identifier (specimen number) omitted, refer to the sample set as a whole. For example,

P-5-7 referred to the sample set with PSL members, 5:1 span:depth ratio, and a 4D loaded

edge distance.

4.2 Connection Tests

A total of one-hundred-twenty connection specimens were tested, with testing

variables of connection main member material, span:depth ratio of the connection main

member, and loaded edge distance of the connection in the main member. Sample sizes

for each tested combination of variables, are summarized in Table 3-1. Load

displacement curves for each connection test are included in Appendix A. Connection

test data for each specimen is presented in Appendix B.

Three different failure modes were observed at capacity, which will be referred to

by the following designations and definitions:

• “S” – Splitting of the connection main member with little or no sign of crushing

evident in the area of the bolt hole. The split (or crack) propagated from the

lower third of the bolt hole. No plastic deformation occurred in the steel side

members, bolt, nut, or washer. A typical center section depicting this mode, with

the splits highlighted with marker, is shown in Figure 4-1a.


• “Im-S” - Mixed mode characterized by a combination of Mode Im failure as

defined by NDS/TR-12, and splitting “S” as defined above. Splitting propagated

from the lower third of the bolt hole, and significant evidence of bearing failure in

the main member beneath the bolt hole was observed. Bulges of wood material

were also common beneath the connection, due to the displacement of the crushed

wood material. No plastic deformation occurred in the steel side members, bolt,

nut, or washer. A typical center section depicting this mode, with the splits

highlighted with marker, is shown in Figure 4-1b.

• “IIIs-S” – Mixed mode characterized by a combination of Mode IIIs failure as

defined by NDS/TR-12, and “Mode S” splitting as defined above. Splitting

propagated from the lower third of the bolt hole, significant evidence of bearing

failure in the main member beneath the bolt hole, and development of a single

plastic hinge in the bolt occurred. Figure 4-1c shows a bolt with a developed

plastic hinge, which is evident by the background lighting visible underneath the

center of the unthreaded shank with the bolt resting on a horizontal surface.

Bulges of wood material were also common beneath the connection, due to the

displacement of the crushed wood material. No plastic deformation occurred in

the steel side members, nut, or washer. A typical center section with the splits

highlighted in marker, depicts this mode in Figure 4-1d.

Figure 4-1a: Main Member of Typical Figure 4-1b: Main Member of Typical Mode S Failure Mode Is-S Failure


Figure 4-1c: Bolt of Typical Mode Figure 4-1d: Main Member of Typical IIIs-S Failure Mode IIIs-S Failure

A summary of the failure modes observed is presented in Table 4-1. For sets that

observed more than one type of failure mode, the modes are listed with the most

frequently occurring mode first. In general, Mode S failures occurred at the 4D loaded

edge distance for all materials, regardless of span:depth ratio. The two mixed modes,

Mode Is-S and Mode IIIs-S, occurred in cases with 7D and 10D loaded edge distances. In

these cases the increased loaded edge allowed for connection resistances to be attained

that induced bearing failure in the main member, and developed a plastic hinge in the bolt

at the largest loaded edge distance. The connection detail was expected to exhibit

NDS/TR-12 Mode Im behavior up to capacity, regardless of the connection loaded edge

distance or main member span:depth ratio. While precise behavior of the main member

at capacity could not be determined due to the presence of the steel side plates, because

failure was defined as only a ten percent reduction from capacity, it is reasonable to

assume that the observed mechanisms at failure were similar to those present at the

capacity resistance of the connection.


Table 4-1: Failure Modes Observed During Connection Testing (after Smart 2002)

4 7 1010:1 S5:1 S, Im-S Im-S Im-S, IIIs-S3:1 S, Im-S

10:1 S5:1 S Im-S, S IIIs-S3:1 S

10:1 S5:1 S, Im-S Im-S Im-S, IIIs-S3:1 Im-S, S

PSL

Loaded Edge Distance (D)Span:Depth Material Ratio

MSR

LVL

Note: In cells with more than one listing, modes are listed

As defined previously, a considerable amount of splitting (alternately referred to

in order by frequency of occurrence.

as cracking) occurred for each of the failure modes observed. A representative case of

the observed splitting is depicted in Figure 4-2, with the split highlighted by marker for

visibility. Splitting typically propagated parallel to the grain orientation for MSR lumber

connection specimens, and longitudinally for LVL and PSL connection specimens. As

described in Section 3.4.5, horizontal lengths of the splits were measured and recorded

immediately following each connection test. A summary of these crack length

measurements, by connection group, is given in Table 4-2. Average splitting lengths

ranged from 4.0 in. up to 19.0 in., with associated COVs ranging from approximately

13% to 45%. No apparent trends were detected in splitting lengths, with respect to main

member material, span:depth ratio, or loaded edge distance.


Figure 4-2: Representative Specimen with Splitting Propagation Highlighted (MSR Shown)

Table 4-2: Average Splitting Lengths with Associated COVs

4 7 10 4 7 10 4 7 10Average 20.7 11.7 11.0

COV 14.9% 17.4% 20.5%Average 6.3 18.9 19.0 8.0 12.6 14.5 10.4 13.0 13.8

COV 45.0% 24.0% 18.8% 22.7% 23.5% 21.8% 14.9% 19.9% 23.5%Average 4.0 9.2 8.7

COV 13.1% 35.5% 20.5%

Span

: D

epth

R

atio

10

5

3

MSR LVL PSL

Splitting Length (in)Loaded Edge Distance Loaded Edge Distance Loaded Edge Distance

A summary of observed 5% offset yield and capacity resistances, with associated

COVs, is provided in Table 4-3. Resistances at the 5% offset yield level ranged from a

minimum of 2095 pounds for PSL with a 4D loaded edge distance and main member

span:depth ratio of 5:1, to 3548 pounds for LVL with a 10D loaded edge distance and

main member span:depth ratio of 5:1. Associated COVs were generally highest for MSR

lumber, followed by PSL and LVL. Resistances at the capacity level ranged from 2624

pounds for MSR lumber with a 4D loaded edge distance and main member span:depth

ratio of 5:1, up to 7146 pounds for PSL with a 10D loaded edge distance and main

member span:depth ratio of 5:1. Similar to the 5% offset yield level, COVs of capacity

resistances were generally higher for MSR lumber, followed by PSL and LVL. At both


5% offset yield and capacity levels, varying main member span:depth ratios had a

negligible affect on resistance values. Another consistent trend observed for both

resistance levels, was an increase in resistance with increasing loaded edge distance.

This followed intuition that with more material below the connection, the connection

could resist greater loads.

Table 4-3: Average 5% Offset Yield and Capacity Resistance Values, with Associated COVs

4 7 10 4 7 10 4 7 10Average 2784 2760 2406

COV 24.2% 10.8% 15.9%Average 2133 2994 3317 2513 3273 3548 2095 2710 3082

COV 25.4% 27.3% 7.7% 4.5% 9.8% 7.5% 17.6% 12.5% 18.8%Average 2218 2434 2343

COV 33.2% 9.4% 20.1%

4 7 10 4 7 10 4 7 10Average 3277 2935 3378

COV 27.6% 10.8% 11.6%Average 2624 4153 5939 2804 4462 6672 3008 4822 7146

COV 27.1% 21.6% 12.0% 7.7% 12.1% 6.5% 12.9% 8.5% 7.1%Average 2872 2700 3145

COV 35.8% 6.1% 11.6%

5% Offset Yield (lb)Loaded Edge Distance

MSRLoaded Edge Distance

Span

: D

epth

R

atio

10

5

3

Capacity (lb)Loaded Edge Distance

Span

: D

epth

R

atio

10

5

3


PSLLoaded Edge Distance


LVL

Resistances at the 5% offset yield and capacity levels were compared using a

linear regression format utilized by Smart (2002). This is illustrated in Figure 4-3, which

includes regressions grouped by connection main member material type. Regression

relationships were the following:

MSR: Pult = 1.3912 * P5%offset (4-1)

LVL: Pult = 1.3508 * P5%offset (4-2)

PSL: Pult = 1.6889 * P5%offset (4-3)

The regression equations indicate that MSR lumber and LVL connections had a similar

relationship, with capacity resistance approximately 1.4 times the 5% offset yield

resistance. For PSL, capacity resistance was approximately 1.7 times the 5% offset yield


resistance. The R-squared values for these regressions, a measure of goodness of fit,

were 0.6942 for MSR lumber, 0.5355 for LVL, and 0.4976 for PSL, respectively. These

R2 values indicated a relatively good correlation between capacity resistance and 5%

offset yield resistance.

y = 1.3912xR2 = 0.6942

y = 1.3508xR2 = 0.5355

y = 1.6889xR2 = 0.4976

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 1000 2000 3000 4000 5000

5% Offset Yield Resistance (lb)

Cap

acity

Res

ista

nce

(lb)

MSRLVLPSLLinear (MSR)Linear (LVL)Linear (PSL)

MSR

LVL

PSL

Figure 4-3: Capacity Resistance vs. 5% Offset Yield Resistance, with Linear Regressions (after Smart 2002)

A summary of elastic stiffness, connection slip at 5% offset yield and capacity

resistances, and ductility ratios, is provided in Table 4-4. Elastic stiffness values ranged

from approximately 35,000 lb/in, to 71,000 lb/in. MSR lumber generally had higher

elastic stiffness than LVL and PSL. Variable loaded edge distances did not affect the

elastic stiffness values. Connection slips ranged from approximately 0.060 in. to 0.115

in. at the 5% offset yield resistance level, and from approximately 0.120 in. to 0.660 in. at

capacity resistance. The composite materials, LVL and PSL, generally had larger slip

values in comparison with MSR lumber. 5% offset yield connection slips for connections

with 7D and 10D loaded edges were typically slightly larger than those with the

minimum 4D loaded edge distance. At capacity, connection slips increased regularly

with each increasing loaded edge distance, especially for connections with composite


materials. Ductility ratios ranged from approximately 1.50 to 5.70. Ductility ratios

consistently increased with each increasing loaded edge distance, for each material. PSL

had significantly higher ductility ratios in comparison with MSR lumber and LVL.

Overall, varying span:depth ratio of the connection main member yielded no noticeable

trends on stiffness, connection slip, or ductility ratios.

Table 4-4: Average Elastic Stiffness, Connection Slip at 5% Offset Yield and Capacity, and Ductility Ratio, for Connection Test Groups

4 7 10 4 7 10 4 7 1010 Average 71263 43585 556085 Average 48037 50856 59062 49641 45400 48171 39362 38515 358263 Average 61814 43283 39678

4 7 10 4 7 10 4 7 105% Offset 0.072 0.093 0.072Capacity 0.117 0.144 0.244

5% Offset 0.073 0.091 0.090 0.082 0.110 0.106 0.075 0.102 0.115Capacity 0.145 0.238 0.411 0.142 0.258 0.472 0.220 0.378 0.656

5% Offset 0.060 0.080 0.087Capacity 0.130 0.123 0.288

4 7 10 4 7 10 4 7 1010 Average 1.63 1.54 3.355 Average 1.97 2.70 4.60 1.87 2.40 4.46 2.93 3.84 5.703 Average 2.08 1.54 3.33

Ductility Ratio

Elastic Stiffness (lb/in)Loaded Edge Distance Loaded Edge Distance

Span

: D

epth

R

atio

10

5

3




LVL

Connection Slip (in) Loaded Edge Distance

Span

: D

epth

MSR

Loaded Edge Distance Loaded Edge Distance Loaded Edge Distance

Span

: D

epth

Average load-displacement plots were constructed for each set of connection

configuration variables. Figures 4-4 through 4-6 show average load-displacement plot

comparisons arranged by material type, for variable main member span:depth ratio and

4D loaded edge. No noticeable difference between curves was detected for varying

span:depth ratios, with the exception of MSR at the 10:1 span:depth ratio, which reached

a significantly higher capacity than the lower span:depth ratio connection groups.

Figures 4-7 through 4-9 show average load-displacement plot comparisons arranged by

material type, for variable loaded edge distance. The general trend illustrated in each

figure was an increase in resistance and ductility, as the loaded edge distance was

increased. Figures 4-10 through 4-12 show average load-displacement plot comparisons


arranged by loaded edge distance, for variable main member material type. No

noticeable difference between material curves was detected in comparisons between at

the 4D and 7D loaded edge distance. However, at the 10D loaded edge distance, PSL

and LVL both achieved higher resistances and were more ductile, in comparison with

MSR.

0

1000

2000

3000

4000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

M-10-4M-5-4M-3-4

Figure 4-4: Average Load-Displacement Plots for MSR Connections with 4D Loaded Edge

Distance and Variable Main Member Span:Depth Ratio


0

1000

2000

3000

4000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

itanc

e (lb

)

L-10-4L-5-4L-3-4

Figure 4-5: Average Load-Displacement Plots for LVL Connections with 4D Loaded Edge


0

1000

2000

3000

4000

- 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

P-10-4P-5-4P-3-4

Figure 4-6: Average Load-Displacement Plots for PSL Connections with 4D Loaded Edge



0

1000

2000

3000

4000

5000

6000

7000

8000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

M-5-4M-5-7M-5-10

Figure 4-7: Average Load-Displacement Plots for MSR Connections with 5:1 Main Member

Span:Depth Ratio and Variable Loaded Edge Distance

0

1000

2000

3000

4000

5000

6000

7000

8000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

L-5-4L-5-7L-5-10

Figure 4-8: Average Load-Displacement Plots for LVL Connections with 5:1 Main Member



0

1000

2000

3000

4000

5000

6000

7000

8000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

P-5-4P-5-7P-5-10

Figure 4-9: Average Load-Displacement Plots for PSL Connections with 5:1 Main Member


0

1000

2000

3000

4000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

M-5-4L-5-4P-5-4

Figure 4-10: Average Load-Displacement Plots for Connections with 5:1 Main Member

Span:Depth Ratio, 4D Loaded Edge Distance and Variable Main Member Material


0

1000

2000

3000

4000

5000

6000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

M-5-7L-5-7P-5-7



0

1000

2000

3000

4000

5000

6000

7000

8000

0.00 0.15 0.30 0.45 0.60 0.75

Slip (in)

Res

ista

nce

(lb)

M-5-10L-5-10P-5-10




4.2.1 Connection Test Subset – Continuously Supported Case

A smaller subset of continuously supported specimens (i.e. main member

span:depth of 0:1), was also tested, as summarized in Table 3-1. Given the intent of the

subset to serve as a preliminary investigation into the continuously supported case, and

with the reduced sample size, the scope of commentary in this section has been limited to

the failure behavior observed, and resistances measured at 5% offset yield and capacity

levels. Load displacement curves for this subset are provided in Appendix A. Test data

is presented in Appendix B.

In all cases, the failure mode observed at capacity characterized Mode IIIs

behavior defined by NDS/TR-12. As described in Section 2.2.3, the apparent failure

mechanism consisted of the formation of a plastic hinge in the fastener at each shear

plane of the connection, and bearing failure of the main member of the connection. A

typical center section and bolt, depicts this mode in Figure 4-13. A summary of the

failure modes observed is presented in Table 4-5.

Figure 4-13: Bolt and Main Member of Typical Mode IIIs Failure


Table 4-5: Failure Modes Observed During Continuously Supported Connection Testing (after Smart 2002)

4 7MSR IIIs IIIs

LVL IIIs IIIs

PSL IIIs IIIs

Loaded Edge Distance (D)Material

A summary of observed 5% offset yield and capacity resistances, with associated

COVs, is provided in Table 4-6. Resistances at the 5% offset yield level ranged from a

minimum of approximately 2200 pounds to 3800 pounds. Resistances at capacity ranged

from approximately 6400 pounds to 9600 pounds. At both resistance levels, no

consistent trend was observed on the effect of varying the loaded edge distance of the

connection. In comparison with Table 4-3, there was no noticeable difference in 5%

offset yield resistance observed in comparing the main connection testing program with

the continuously supported subset. At capacity resistance, however, continuously

supported specimens attained considerably higher values than those of the main

connection testing program.

Table 4-6: Average 5% Offset and Capacity Resistance Values, with Associated COVs, for Continuously Supported Connection Specimens

4 7 4 7 4 72588 2202 3500 3763 2474 3087

13.0% 16.0% 5.6% 6.8% 11.3% 5.7%

4 7 4 7 4 79553 6359 8932 8758 9033 9090

21.1% 5.6% 14.7% 5.5% 12.0% 8.9%

MSRLoaded Edge (D)

AverageCOV

5% Offset Yield (lb)Loaded Edge (D)

Loaded Edge (D)

PSLLoaded Edge (D)

Loaded Edge (D)

LVL

AverageCOV

Capacity (lb)Loaded Edge (D)

4.3 Material Property Tests

Material property tests were conducted following the guidelines described in

Section 3.5, and in the sequence illustrated in Figure 3-1.


4.3.1 Shear Modulus Tests

As described in Section 3.5.1, ten specimens of each material type were tested to

determine the representative shear modulus. Similar to the trend observed by Harrison

(2006), the torsion test configuration was suited for the dimensionally stable composite

specimens (LVL and PSL). However, dimensional defects present in the MSR lumber

prohibited those specimens from being secured into end grips with both ends initially

vertical. This deviation of testing procedure was deemed allowable, as adjusting the

clamps to straighten the specimen would induce an additional amount of stress in the

specimen. An example of torque-angular rotation data collected from testing, is provided

in Appendix E, for each of the three materials. A tabulated summary of all shear

modulus test results is provided in Appendix E.

Table 4-7: Average Shear Modulus and Associated COVs

MSR LVL PSLAverage (psi) 1.66E+05 1.04E+05 9.83E+04

COV 22.2% 10.8% 4.3%

Shear Modulus (G)

Average shear modulus values, with associated COVs, are presented in Table 4-7.

Average shear modulus values were 1.66x105 psi for MSR lumber, 1.04x105 psi for LVL,

and 9.83x104 psi for PSL. Associated COV values were 22.2%, 10.8%, and 4.3%,

respectively. The COVs of the composite specimens (LVL and PSL) were lower than

that determined for the MSR specimens. This was expected due to the improved

regularity of wood-based composite materials in terms of strength-affecting defects

(Smulski 1997). This same trend was also observed in shear modulus research performed

by Harrison (2006).

4.3.2 Modulus of Elasticity Tests

Ten specimens of each material type, were tested following the procedures

described in Section 3.5.2, to determine modulus of elasticity. An example of load-

displacement data collected from testing, is provided in Appendix E, for each of the three


materials. A tabulated summary of all modulus of elasticity results is provided in

Appendix E.

Table 4-8: Average Modulus of Elasticity and Associated COVs

MSR LVL PSLAverage (psi) 1.90E+06 2.33E+06 2.21E+06

COV 18.6% 9.2% 14.2%

Modulus of Elasticity (E)

Average modulus of elasticity values, with associated COVs, are presented in

Table 4-8. Average modulus of elasticity values were 1.90x106 psi for MSR lumber,

2.33x106 psi for LVL, and 2.21x106 psi for PSL. Corresponding COVs were 18.6%,

9.2%, and 14.2%, respectively. The rated modulus of elasticity value of all three

materials, which was given in either the 2005 NDS or the manufacturer’s design

literature, was 2.0x106 psi. Calculated values of LVL and PSL modulus of elasticity

were greater than their corresponding rated values. The calculated MSR lumber modulus

of elasticity was 5% lower than its rated value, which was judged to be acceptable due to

the reasonable COV observed in the sample set of MSR specimen data.

4.3.3 Dowel Embedment Tests

Dowel embedment strengths at the 5% offset yield point and capacity, were

determined as described in Section 3.5.3, using the full-hole test configuration.

Specimens were taken from tested connection test specimens, from undamaged regions in

as close proximity as possible to the location of the connection bolt hole. A total of 40

dowel embedment specimens for each material, one from each connection test specimen,

were tested. A representative sample of load-displacement data collected from dowel

embedment testing, is provided in Appendix E, for each of the three materials. A

tabulated summary of all dowel embedment test results is provided in Appendix E.

An issue that was encountered, predominantly with the MSR lumber specimens

but also in several of the PSL type specimens, involved how to define the ultimate load in

cases where the load continually increased throughout the test. During testing, a

displacement limit of 1-in., a magnitude that was decided upon arbitrarily, was used as


the cut-off point for each test if the maximum load had not yet been obtained. However,

when each load-displacement curve was investigated, in some cases the behavior was an

initial relatively linear response, followed by softening for a substantial amount of

displacement, and ending with an increasingly growing resistance due to compaction of

the growth rings, with no achievement of capacity. Due to this compaction behavior,

which resulted in a resistance increases of up to 30-40% in the range between

displacements of 0.75 inch and 1.00 inch, it was decided that a displacement limit of 0.75

inch was more appropriate to be used as the definition of capacity load if it had not been

obtained prior during the test. The importance of this decision should be noted, as the

capacity level dowel embedment strength has a direct effect on predicting connection

capacity with the TR-12 model equations. A representative load-displacement curve of

this compaction behavior at large displacements, is provided in Appendix E.

An additional issue encountered with the MSR lumber at large test displacements

involved several specimen strengths exceeding that of the 10,000 lb load cell. This

initially occurred early in the testing of MSR lumber specimens, and was remedied by

using a 20,000 lb load cell for the remaining MSR lumber specimens. Back-up

specimens were retested in cases that had originally exceeded load cell capacity. The

10,000 lb load cell was adequate for LVL and PSL specimens, which had been tested

prior to the MSR lumber specimens.

Average dowel embedment strength values, with associated COVs, are presented

in Table 4-9. At 5% offset yield, LVL had the highest dowel embedment strength,

followed by MSR lumber and PSL. At capacity, MSR had the highest dowel embedment

strength, with the composite materials approximately the same. At both load levels,

COVs for MSR lumber were significantly higher than those of the composite materials.

Again, this trend was expected due to the improved homogeneity of wood-based

composite materials, over solid sawn lumber (Smulski 1997).


Table 4-9: Average Dowel Embedment Strengths and Associated COVs

MSR LVL PSLAverage 3477 4379 3210

COV 31.6% 10.6% 16.7%

Average 6550 5943 6063COV 30.9% 12.0% 17.5%

5% Offset Yield

Capacity1

MaterialEmbedment Strength (psi)

1 – Displacement limit of 0.75 in. used to define capacity, if max load had not been achieved prior

in testing

Average 5% offset yield embedment strength values were also compared with the

NDS predicted embedment strengths calculated from Equation 2-3, which predicts

embedment strength as a function of material specific gravity and dowel diameter. For

specific gravity, the experimentally determined value for MSR lumber was used. For

LVL and PSL, the equivalent specific gravity of 0.50 was used, in lieu of the

experimentally determined value, as per the manufacturers’ design literature (Boise EWP

2006 and iLevel 2006). Average 5% offset yield embedment strengths from

experimental tests, NDS predicted values, and a ratio between predicted and test values,

are given in Table 4-10. For MSR lumber, the NDS embedment strength equation

slightly over-predicted embedment strength at 5% offset yield. Using the equivalent

specific gravity, the NDS embedment strength equation accurately predicted 5% offset

yield embedment strength for PSL, and was conservative for LVL.

Table 4-10: 5% Offset Yield Embedment Strengths – Average Test Values, NDS Predicted Values, and Ratio Comparisons of NDS Predicted Values to Average Test Values

MSR LVL PSLAvg. Test Value 3477 4379 3210NDS Predicted 3672 3158 3158

NDS / Test 1.06 0.72 0.98

MaterialEmbedment Strength - 5% Offset (psi)

4.3.4 Bolt Bending Strength Tests

A total of 10 bolt specimens were tested, following the procedure outlined in

Section 3.5.4. Analysis of the load displacement data produced the 5% offset yield and


capacity resistance values. These values were then used to calculate the corresponding

bending yield strength, Fyb. The average bending yield strength was used in the yield

model calculations to determine theoretical connection resistance. A representative

example of a plotted load displacement with 5% offset analysis, is provided in Appendix

-E.

The average bending yield strengths for 5% offset yield and capacity, along with

corresponding COVs, are shown below in Table 4-11. The capacity and 5% offset yield

loads, corresponding plastic moments, and corresponding bending yield strengths, are

summarized for each specimen in Appendix E. Bending yield strengths are not predicted

by the NDS or TR-12, therefore a comparison between experimental and predicted values

has not been included.

Table 4-11: Bending Yield Strength (Fyb) Results

5% Offset Yield (psi) Capacity (psi) Average: 72160 85570 1/2" Nominal

Diameter COV: 7.2% 6.6%

4.3.5 Tension Perpendicular to Grain Tests

Guidelines outlined in Section 3.5.5 were followed in the testing of tension

perpendicular to grain strength. A total of 120 specimens, 40 specimens of each material

type, were tested. A summary of specimen dimensions, maximum loads, and tension

perpendicular to grain strengths, is provided in Appendix E. Representative load

displacement data for each material, is also included in Appendix E.

The average tensile strength perpendicular to grain, along with associated COVs,

are shown below in Table 4-12. The tension strength perpendicular to grain of MSR

lumber, 327 psi, was significantly higher than that of LVL and PSL (110 and 147 psi,

respectively). As was found in the research of Hummer et al. (2006), LVL strength was

substantially lower than that of solid lumber, with approximately the same level of

variance in strength values. This study found the same trend for PSL in comparison with

MSR lumber. As described by Hummer et al. (2006), a probably source of the decreased

strength of the composite materials is that ‘the veneers used in the manufacture of the

product possess lath checks, which allow the veneer to split easily’.


Table 4-12: Average Tensile Strengths Perpendicular to Grain (tf ) and Associated COVs

MSR LVL PSLAverage (psi) 327 110 147

COV 28.2% 26.1% 32.4%

Material

4.3.6 Mode I Fracture Tests

Mode I fracture energy was determined according to the test methods described in

Section 3.5.6. A total of 120 specimens, 40 specimens of each material type, were tested.

Indentation test results of un-cracked calibration specimens revealed that embedment due

to the loading pins contributed to less than one-tenth of one percent of the displacement

measurements. This minor contribution was considered negligible, and as such the

experimental load displacement data was not corrected for loading pin embedment. An

example of load displacement data collected from testing, is provided in Appendix E, for

each of the three materials. A tabulated summary of all mode I fracture test results is

provided in Appendix E.

The average mode I fracture energy, along with associated COVs, are shown

below in Table 4-13. Fracture energies were higher for the composite materials, 14.18

and 7.62 lb-in/in2 for PSL and LVL, respectively, than that of MSR lumber, at 4.37 lb-

in/in2. This translates to the composite materials exhibiting more ductile behavior, while

solid wood behave in a more brittle manner. PSL had a particularly high fracture energy

due to the number of strand boundaries and presence of voids in the cross section, which

combine to offer greater resistance to crack propagation and load-carrying capacity past

initial fracture (Ehart et al. 1998).

Table 4-13: Average Mode I Fracture Energy (GIf) and Associated COVs

MSR LVL PSLAverage

(lb-in/in2)4.37 7.62 14.18

COV 48.1% 26.0% 32.8%

Material


4.3.7 Moisture Content and Specific Gravity Tests

After connection testing, full-thickness blocks cut to approximately 1” by 1”

dimensions were cut from each specimen in close proximity to the connection location.

Procedures described in Section 3.5.7 were then followed to determine the moisture

content and specific gravity. A total of 40 specimens were tested for each material, one

from each connection test specimen. A tabulated summary of all data collected for

determination of moisture content and specific gravity, is provide in Appendix E.

Average moisture content and specific gravity values, with associated COVs, are

presented in Table 4-14. MSR lumber equilibrated at 11.9% moisture content, which was

within one tenth of a percent of the calculated equilibrium moisture content (EMC) for

solid wood (12.0%), for the conditions maintained in the environmental chamber. LVL

and PSL had average moisture contents of 9.6% and 8.9% respectively. It was expected

that the wood composites would equilibrate to a lower moisture content than that of solid

wood, due to the heat treating and pressing that occurs during manufacture, and also the

addition of resins to the material. (Bowyer et al. 2003) COV values for the average

moisture contents were 9.4% for MSR lumber, 4.2% for LVL, and 5.1% for PSL.

The average specific gravity for the MSR lumber was 0.56 with a COV of 13.2%.

This value was within two percent of the published design value of 0.57 (AF&PA 2005).

Average specific gravity values for the composites were 0.64 for LVL and 0.63 for PSL,

with respective COVs of 4.3% and 4.5%. These specific gravities were expected to be

higher in comparison to MSR lumber, due to densification during manufacturing of the

product, and ‘presence of adhesive bond lines between veneer’ and strand layers

(Harrison 2006).

Table 4-14: Average Moisture Content and Specific Gravity Results, with Associated COVs

Material MSR LVL PSLMoisture Content

(COV)11.9% (9.4%)

9.6% (4.2%)

8.9% (5.1%)

Specific Gravity (COV)

0.56 (13.2%)

0.64 (4.3%)

0.63 (4.5%)


4.4 Evaluation of TR-12

Theoretical resistances were calculated at 5% offset yield and capacity using the

yield theory-based TR-12 general equations (Equations 2-4 to 2-7, as listed in Section

2.2.3). The experimentally determined dowel embedment and bolt bending strengths,

along with the experimental connection geometries, were inserted as inputs into the TR-

12 equations, to predict 5% offset yield and capacity resistance of each individual

specimen. Load duration was previously accounted for in experimental dowel

embedment values, which were obtained from tests lasting approximately 10 minutes in

duration. For the prediction of 5% offset yield resistance, the 5% offset yield values for

dowel embedment and bolt bending strength were used. For the prediction of capacity

resistance, the capacity strength values for dowel embedment and bolt bending strength

were used. Calculations were based upon the fundamental assumption of consistent yield

mode behavior at both 5% offset yield and capacity resistance levels following one of the

yield modes considered by yield theory (Figure 2-1), while the behavior at failure could

differ significantly. Possible differences included splitting of the wood member, and or

the development of ‘a shear plug, fastener shear, or fastener withdrawal’ (AF&PA 1999).

Theoretical resistances were compared to experimental test results using the

‘calculated-to-tested ratios’ (C/T ratios) format utilized by Smart (2002). NDS and

LRFD nominal lateral design values were also calculated from predicted 5% offset yield

resistances. A summary of individual factors of safety, over-strengths, and design factors

of safety, were then calculated by comparing respective nominal lateral design values

with experimental test results.

4.4.1 TR-12 Theoretical Lateral Connection Resistance Values

A summary of calculated average theoretical 5% offset yield and capacity

resistance values, with associated COVs, is provided in Table 4-15. Theoretical 5%

offset yield resistances ranged from approximately 2050 pounds to 2600 pounds.

Theoretical capacity resistances ranged from approximately 4300 pounds to 6000 pounds.

At both resistance levels, associated COVs for MSR lumber were generally higher than

those of LVL and PSL. This was due to corresponding variances in the dowel

embedment strengths, which were used as inputs to calculate theoretical values. It should


be noted that where a trend of resistances increasing with larger loaded edge distances

existed in connection test results, the same trend was not evident in theoretical resistance

values. This difference was due to the loaded edge distance not being accounted for by

the TR-12 equations. A tabulated summary of all theoretical lateral connection resistance

values is provided in Appendix C.

Table 4-15: Average TR-12 Lateral Connection Resistance Values at 5% Offset Yield and Capacity, with Associated COVs

4 7 10 4 7 10 4 7 10Average 3028 3325 2366

COV 32.7% 13.8% 18.3%Average 2203 2801 2856 3331 3259 3624 2459 2409 2600

COV 37.9% 36.1% 21.6% 6.5% 10.8% 9.1% 9.2% 19.3% 17.5%Average 2363 3637 2057

COV 34.9% 11.0% 7.3%Average 2383 2172 3458 3483 2575 2880

COV 1.7% 14.1% 10.4% 9.7% 13.7% 9.1%

4 7 10 4 7 10 4 7 10Average 4919 4841 4601

COV 37.3% 8.9% 20.3%Average 5376 4979 4420 4568 4640 4913 4260 4313 4597

COV 31.1% 22.2% 25.7% 16.3% 14.3% 12.5% 17.6% 18.9% 18.9%Average 5970 4481 4770

COV 34.6% 10.5% 16.4%Average 4438 4314 4554 4581 4945 5029

COV 37.4% 8.8% 12.2% 11.9% 20.5% 3.8%




LVL

Capacity (lb)Loaded Edge Distance

0

3

Span

: D

epth

Rat

io 10

5

3

0

5

10

Span

: D

epth

Rat

io

5% Offset Yield (lb)Loaded Edge Distance

MSRLoaded Edge Distance

Theoretical resistances at the 5% offset yield and capacity levels were also

compared using a linear regression format, similar to that shown in Figure 4-3. However,

associated R-squared values were relatively close to zero, indicating poor goodness of fit.

Therefore, the linear regression analysis of the theoretical resistances has been omitted.

NDS ASD lateral design values were also calculated, according to the equations

outlined in Section 2.2.3.1 (Table 4-16). As stated previously, the lateral design value

was the minimum of the reference lateral design value (RLDV), calculated from the


predicted TR-12 5% offset yield resistance (Equation 2-11), and the allowable design

shear value (Equations 2-8 and 2-9) (which was converted to a maximum connection

resistance for the sake of comparison). Both the RLDV and the allowable design shear

values were adjusted to the 10-minute load duration by being multiplied by the 1.6 load

duration factor. In general, the NDS lateral design value was controlled by the RLDV

for the connection sets with a span:depth of 10:1 and 4D loaded edge, as well as sets with

a 5:1 span:depth and 10D loaded edge. The continuously supported connection sets were

also controlled by the RLDV, since the design shear check equations were not applicable.

The allowable design shear values controlled in all other cases, with the single exception

being LVL connections with a 5:1 span:depth and 7D loaded edge. It must be noted that

the allowable design shear values were quite low in comparison with corresponding

RLDVs, for connection sets with a 4D loaded edge and either a 5:1 or 3:1 span:depth

ratio. This was due to these sets having a smaller loaded edge distance in comparison to

the member depth, and the allowable design shear value being calculated as a function of

the squared ratio of the two values.

Table 4-16: NDS ASD Lateral Design Values (Defined as Minimum of RLDV and Allowable Shear Check – Shown in Bold)

4 7 10 4 7 10 4 7 10RLDV 916 758 758Shear4 1216 1824 1856RLDV 916 916 916 758 758 758 758 758 758Shear4 93 496 1446 139 744 2169 141 757 2207RLDV 916 758 758Shear4 93 139 141RLDV 916 916 758 758 758 758Shear4

1 Specific Gravity = 0.57, Fv = 190 psi (AF&PA 2005)2 Equivalent Specific Gravity = 0.50, Fv = 285 psi (Boise EWP 2006)3 Equivalent Specific Gravity = 0.50, Fv = 290 psi (iLevel 2006)4 Values shown in terms of connection resistance, P (where P = 2*V)

MSR1 LVL2 PSL3

Design Value (lb)Loaded Edge (D) Loaded Edge (D) Loaded Edge (D)

Span

: D

epth

Rat

io

10

5

3

0


4.4.2 Comparison of Theoretical (Calculated) Values to Test Values

Comparisons between theoretical and test values were made using C/T ratios, as

defined in Section 4.4. A tabulated summary of all C/T ratio results is provided in

Appendix C. Therefore, the following deductions were made for corresponding C/T ratio

values:

C/T ratio < 1.0 : Model conservatively predicted connection resistance.

C/T ratio ≈ 1.0 : Model accurately predicted connection resistance.

C/T ratio > 1.0 : Model over-predicted connection resistance.

Statistical comparisons were performed on average set C/T ratios and associated

COVs, between connection sets with comparable variables. This was done in the form of

a single-factor repeated measures analysis of variance (ANOVA), using an alpha level α

= 0.05. The null hypothesis was that there was no significant difference between set

averages. If at least one mean was detected as significantly different (p-value < α), a

subsequent Tukey’s Honestly Significant Difference (HSD) multiple comparisons

analysis was performed to determine the relationship between set averages.

4.4.2.1 Comparisons with Variable Span:Depth Ratios

The effect of varying span:depth was investigated by statistically comparing

average C/T ratios of connection sets with the same main member material type and

loaded edge distance (4D). Tables 4-17 through 4-19 include the average C/T ratios,

associated COVs, and statistics for each material group of connection sets.

At 5% offset yield resistance, average C/T ratios ranged from 0.91 to 1.51. No

statistical difference between C/T ratios was detected within MSR lumber and PSL

groups. LVL at the minimum span:depth ratio of 3:1, had a significantly higher C/T ratio

that at the maximum span:depth ratio of 10:1.

At capacity resistance, average C/T ratios ranged from 1.40 to 2.14, indicating

that the model over-predicted capacity in all cases. No statistical difference between C/T

ratios was detected within LVL and PSL groups. MSR lumber C/T ratios at 3:1

span:depth were significantly larger than those at 10:1 span:depth. It should also be

noted that in all cases, C/T ratios at capacity were higher than corresponding values at 5%

offset yield.


Table 4-17: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for MSR Connection Sets with Variable Span:Depth Ratio (with Detected Statistical

Differences Highlighted)

M-10-4 M-5-4 M-3-4 M-10-4 M-5-4 M-3-4Average 1.08 1.02 1.09 Average 1.49 2.08 2.14

COV 14.0% 17.7% 26.9% COV 18.3% 22.4% 30.4%

Anova p-value Anova p-value

Tukey's Conclusion

Tukey's Conclusion

Set5% Offset

0.8186

No Difference Detected (M-3-4) > (M-10-4)

MSR Connections with 4D Loaded Edge

Capacity Set

0.0166

Table 4-18: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for LVL Connection Sets with Variable Span:Depth Ratio (with Detected Statistical Differences

Highlighted)

L-10-4 L-5-4 L-3-4 L-10-4 L-5-4 L-3-4Average 1.21 1.33 1.51 Average 1.66 1.64 1.67

COV 15.2% 5.8% 15.8% COV 12.4% 19.7% 14.0%


Tukey's Conclusion

Tukey's Conclusion

0.0184 0.978

LVL Connections with 4D Loaded Edge

5% Offset Set Capacity Set

(L-3-4) > (L-10-4) No Difference Detected

Table 4-19: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for PSL Connection Sets with Variable Span:Depth Ratio (with Detected Statistical Differences

Highlighted)

P-10-4 P-5-4 P-3-4 P-10-4 P-5-4 P-3-4Average 1.01 1.21 0.91 Average 1.40 1.46 1.52

COV 27.1% 20.4% 19.5% COV 28.3% 29.6% 14.5%


Tukey's Conclusion

Tukey's Conclusion

PSL Connections with 4D Loaded Edge


0.1187 0.798

No Difference Detected No Difference Detected


4.4.2.2 Comparisons with Variable Loaded Edge Distance

The effect of varying loaded edge distance was investigated by statistically

comparing average C/T ratios of connection sets with the same main member material

type and at a span:depth ratio of 5:1. Tables 4-20 through 4-22 include the average C/T

ratios, associated COVs, and statistics for each material group of connection sets.

Average C/T ratios at 5% offset yield resistance ranged from 0.86 to 1.33. No

statistical difference was detected in C/T ratios of MSR lumber connections with varying

loaded edge distances. LVL C/T ratios at the 4D loaded edge were significantly higher

than those at the 7D and 10D loaded edges. PSL C/T ratios at the 4D loaded edge were

significantly higher than at the 10D loaded edge.

Average C/T ratios at capacity resistance ranged from 0.64 to 2.08. C/T ratios of

MSR lumber connections were significantly higher for each decreasing increment of

loaded edge distance, with 4D > 7D > 10D. LVL and PSL C/T ratios followed the same

trend, where the 4D ratios were significantly higher than the 7D and 10D ratios.

At both resistance levels, with the exception of MSR at 5% offset yield, the

consistent trend for all materials was an increase in C/T ratios with lower loaded edge

distances. This was due to test resistance values that tended to decrease with lower

loaded edge distances, combined with relatively stable theoretical resistance values

across the range of loaded edge distances. Smaller tested values (denominator of the C/T

ratio) equated to large C/T ratios at the lower loaded edge distances.

Table 4-20: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for MSR Connection Sets with Variable Loaded Edge Distance (with Detected Statistical



COV 17.7% 20.8% 18.4% COV 22.4% 9.8% 19.1%


Tukey's Conclusion

Tukey's Conclusion

MSR Connections with 5:1 Span:Depth Ratio


0.3140 0.0000

No Difference Detected (M-5-4) > (M-5-7) > (M-5-10)


Table 4-21: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for LVL Connection Sets with Variable Loaded Edge Distance (with Detected Statistical



COV 5.8% 18.6% 11.0% COV 19.7% 15.8% 8.8%


Tukey's Conclusion

Tukey's Conclusion

LVL Connections with 5:1 Span:Depth Ratio


0.0013 0.0000

(L-5-4) > (L-5-7); (L-5-4) > (L-5-10)

(L-5-4) > (L-5-7); (L-5-4) > (L-5-10)

Table 4-22: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for PSL Connection Sets with Variable Loaded Edge Distance (with Detected Statistical



COV 20.4% 22.1% 20.0% COV 29.6% 21.5% 16.5%


Tukey's Conclusion

Tukey's Conclusion

0.0217 0.0005

(P-5-4) > (P-5-10) (P-5-4) > (P-5-7); (P-5-4) > (P-5-10)

PSL Connections with 5:1 Span:Depth Ratio


4.4.2.3 Comparisons with Variable Material

The influence of varying main member material was investigated by statistically

comparing C/T ratios of connection sets with the same span:depth ratio of 5:1 and each

loaded edge distance. Tables 4-23 through 4-25 include the average C/T ratios,

associated COVs, and statistics for connection sets grouped by matching loaded edge

distance.

C/T ratios at the 5% offset yield resistance ranged from 0.86 to 1.33. No

statistical differences were detected between materials, within the 7D and 10D loaded


edge groups. At the 4D loaded edge distance, the C/T ratio for LVL was significantly

higher than that of MSR lumber.

C/T ratios at the capacity resistance ranged from 0.64 to 2.08. No statistical

difference was detected between materials within the 4D and 10D loaded edge groups.

At the 7D loaded edge distance, MSR lumber had a significantly higher C/T ratio than

PSL.

Table 4-23: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for Connection Sets with 4D Loaded Edge Distance and Variable Material Type (with Detected

Statistical Differences Highlighted)

MSR LVL PSL MSR LVL PSLAverage 1.02 1.33 1.21 Average 2.08 1.64 1.46

COV 17.7% 5.8% 20.4% COV 22.4% 19.7% 29.6%


Tukey's Conclusion

Tukey's Conclusion

Connections with 4D Loaded Edge and 5:1 Span:Depth Ratio


0.0333 0.0546

LVL > MSR No Difference Detected

Table 4-24: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for Connection Sets with 7D Loaded Edge Distance and Variable Material Type (with Detected

Statistical Differences Highlighted)


COV 20.8% 18.6% 22.1% COV 9.8% 15.8% 21.5%


Tukey's Conclusion

Tukey's Conclusion



0.6029 0.0189

No Difference Detected MSR > PSL


Table 4-25: Average TR-12 C/T Ratios, Associated COVs, and Statistical Comparisons for Connection Sets with 10D Loaded Edge Distance and Variable Material Type (with

Detected Statistical Differences Highlighted)


COV 18.4% 11.0% 20.0% COV 19.1% 8.8% 16.5%


Tukey's Conclusion

Tukey's Conclusion



0.1208 0.2452


4.4.2.4 Continuously Supported Subset

C/T ratios were calculated for the continuously supported case (span:depth ratio

of 0:1). However average ratios were not statistically compared due to the reduced

sample size of this subset. Average C/T ratios and associated COVs, are shown in Table

4-26 for connections with a 4D loaded edge distance, and in Table 4-27 for connections

with a 7D loaded edge distance. Similar trends were observed at both loaded edge

distances. At 5% offset yield resistance, C/T ratios were approximately 1.0, while at

capacity, C/T ratios ranged from 0.52 to 0.68. This correlated to TR-12 accurately

predicting 5% offset yield resistance, and conservatively predicting capacity resistance.

Table 4-26: Average TR-12 C/T Ratios and Associated COVs, for Continuously Supported Connections with 4D Loaded Edge Distance

M-0-4 L-0-4 P-0-4 M-0-4 L-0-4 P-0-4Average 0.94 0.99 1.04 Average 0.55 0.52 0.55

COV 12.1% 6.2% 13.5% COV 60.1% 17.3% 16.4%

Continuously Supported Connections with 4D Loaded Edge



Table 4-27: Average TR-12 C/T Ratios and Associated COVs, for Continuously Supported Connections with 7D Loaded Edge Distance


COV 4.7% 13.4% 13.3% COV 10.5% 17.0% 13.0%

Continuously Supported Connections with 7D Loaded Edge


4.4.3 Design Value Comparison

Factors of safety, over-strengths, and design factors of safety, were calculated for

the purposes of relating capacity resistance to current design values. These values were

defined and denoted to be consistent with the work of Smart (2002). Factor of safety

(denoted as Cap/NDS Z) was defined as the ratio of test capacity resistance to the reference

lateral design value, as defined by Equation 2-11. Over-strength (denoted as Cap/LRFD Z)

was defined as the ratio of test capacity resistance to the reference lateral resistance, as

defined by Equation 2-16. Both the nominal design value and reference lateral resistance

were calculated from the test 5% offset yield dowel embedment and dowel bending

strengths. The nominal design value was multiplied by a load duration factor, Cd = 1.6,

to adjust the values to the approximate 10-minute duration of the connection test.

Reference lateral resistances were multiplied by a time effect factor, λ = 1.0, for the same

load duration consideration.

Design factor of safety (denoted as Cap/NDS LDV) was defined as the ratio of test

capacity resistance to the NDS lateral design value, which was defined previously in

Section 4.4.1. For determining NDS lateral design values (shown in Table 4-16), general

NDS and manufacturer design literature reference values for specific gravity and shear

strength were used to calculate dowel embedment strength and adjusted shear parallel to

grain, to determine RLDV and allowable design shear values. Given this, the design

factor of safety represented a comparison between experimental capacity resistance and

the design value that would be calculated by an engineer using only the NDS and

additionally the manufacturer’s design literature if using LVL or PSL. This contrasted

with the factor of safety and over-strength values, which compared experimental capacity


resistance with design values based on experimental 5% offset yield dowel embedment

and dowel bending strengths.

Average factor of safety and over-strength values, with associated COVs, are

presented in Table 4-28. In every case, the factor of safety value was 1.35 times greater

than the associated over-strength value. This difference, which is reflected when directly

comparing Equations 2-10 and 2-14, represented the soft-conversion between 10-minute

duration NDS value, and the 10-minute duration LRFD value. For clear-span connection

specimens, average factor of safety values ranged from 2.34 to 8.76, and over-strengths

ranged from 1.74 to 6.49. Span:depth ratio did not seem to have an effect on either factor

of safety or over-strength values. These values did increase considerably with increasing

loaded edge distance for each material. For example, values at the 10D loaded edge

distance were approximately twice those at the 4D distance. This reflected the previous

trend of experimental resistance values, at both 5% offset yield and capacity resistance,

increasing with higher loaded edge distances. With respect to material type, factor of

safety and over-strength values were generally highest for PSL, followed by MSR

lumber, and LVL having the lowest values. This trend likely resulted from differences

between 5% offset yield and capacity resistance, which Equations 4-1 to 4-3 have shown

that the magnitudes of this resistance difference varied between material types.

For continuously supported specimens (those with span:depth ratio of 0:1), the

same ratio between factor of safety and over-strength values, 1.35, was present. Average

factor of safeties ranged from 7.94 to 12.43, and over-strength values ranged from 5.88 to

9.22. These values were significantly higher in comparison with corresponding clear-

span connections with similar loaded edge distances. A consistent trend was not

observed between span:depth ratio, loaded edge distance, or material type variables.

Design factor of safety values, with associated COVs, are also included in Table

4-28. In cases where only one value is listed for design factor of safety, the NDS lateral

design value was controlled by the RLDV. This was the case for all sets with a 10:1

span:depth and 4D loaded edge, sets with a 5:1 span:depth and 10D loaded edge,

continuously supported (0:1 span:depth) sets. Average design factor of safeties ranged

from 3.58 to 9.43 for the two clear-span groups, and from 7.08 to 11.99 for the


continuously supported groups. Design factor of safety were commonly within

approximately 20% of corresponding factor of safety values.

Table 4-28: Average Factor of Safety, Over-Strength, and Design Factor of Safety Values, with associated COVs

4 7 10 4 7 10 4 7 10Cap/NDS Z 3.44 2.79 4.59

Cap/LRFD Z 2.55 2.07 3.40COV 12.2% 14.8% 19.9%

Cap/NDS LDV 3.58 3.87 4.46COV 27.6% 10.8% 11.6%

Cap/NDS Z 3.84 4.96 6.66 2.64 4.31 5.79 3.85 6.41 8.76Cap/LRFD Z 2.85 3.67 4.94 1.96 3.20 4.29 2.86 4.75 6.49

COV 17.3% 28.2% 14.7% 9.9% 14.3% 10.0% 17.2% 16.7% 14.5%Cap/NDS LDV

1 28.22 (2.86)

8.37 (4.53) 6.48 20.17

(3.70)6.00

(5.89) 8.80 21.33 (3.97)

6.37 (6.36) 9.43

COV 27.1% 21.6% 12.0% 7.7% 12.1% 6.5% 12.9% 8.5% 7.1%Cap/NDS Z 3.99 2.34 4.81

Cap/LRFD Z 2.96 1.74 3.57COV 31.6% 11.6% 15.7%

Cap/NDS LDV1 30.88

(3.14)19.42 (3.56)

22.30 (4.15)

COV 35.8% 6.1% 11.6%Cap/NDS Z 12.43 9.05 8.05 7.94 10.99 9.97

Cap/LRFD Z 9.22 6.71 5.96 5.88 8.15 7.39COV 22.0% 21.3% 4.6% 15.2% 4.1% 17.6%

Cap/NDS LDV 10.43 7.08 11.78 11.55 11.92 11.99COV 21.1% 6.1% 14.7% 5.5% 12.0% 8.9%

5

10

Span

: D

epth

Rat

io


LVL

0

3

Loaded Edge DistanceMSR


1 Design factor of safety valued controlled by allowable design shear. RLDV-based design factor of safety

shown in parenthesis for purpose of comparison

In cases where two design factor of safety values are listed, the NDS lateral

design values were controlled by the allowable design shear term (listed first), and the

design factor of safety calculated from the RLDV was listed in parenthesis for

comparison purposes. This was the case for all connection sets with a 4D loaded and

either a 5:1 or 3:1 span:depth, and sets with a 5:1 span:depth and 7D loaded edge,

because these sets had lower span:depth ratios and loaded edge distances that were less


than half the depth of the main member. Average design factor of safeties ranged from

19.42 to 30.88 for the two connection sets with 4D loaded edge distance and from 6.00 to

8.37 for connection sets with 7D loaded edge distance. These relatively high values

were most likely due to the nature of the allowable shear design calculation, which only

considers the loaded edge area of the connection as effective for shear resistance, and

further reduces the shear value by the squared ratio of the loaded edge distance by the

member depth. This reduction then was considerably larger for the 4D loaded edge

cases, as opposed to the 7D loaded edge case. Corresponding design factor of safeties

based on the RLDV value, were 2.86 to 4.15 for 4D loaded edge connection sets, and

4.53 to 6.36 for 7D loaded edge connection sets. While these values were not technically

relevant because they were not the controlling NDS lateral design values, their

magnitudes do contrast the significant difference between the RLDV and allowable

design shear values. These RLDV-based values were commonly lower than

corresponding factor of safety values, but within approximately 25% in terms of

magnitudes.

4.5 Evaluation of Fracture Models

Theoretical capacity resistances were calculated from both the Van der Put and

Jensen splitting capacity models. The experimentally determined Mode I fracture energy

and shear modulus values were used as inputs in both models, and additionally the

experimentally determined modulus of elasticity and tensile strength perpendicular to

grain values were used as inputs into the Jensen model. Load duration was accounted for

in all material property values, which had been obtained from tests lasting approximately

10 minutes in duration. A summary of all theoretical capacity resistance calculations, for

both the Van der Put and Jensen models, is provided in Appendix D.

C/T ratios, as defined in Sections 4.4 and 4.4.2, were used to compare

experimental test results with theoretical capacity resistances. Eurocode 5 design values

were calculated from Equations 2-24 and 2-25, in order to compare design values with

experimental test results in terms of design factor of safety.


4.5.1 Fracture Model Theoretical Lateral Connection Resistance Values

A summary of average theoretical capacity resistances calculated from both

fracture models, with associated COVs, is provided in Table 4-29. Theoretical capacities

calculated from the Van der Put model, ranged from approximately 4670 pounds to

17580 pounds. Capacity resistances predicted by the Jensen model ranged from

approximately 5150 pounds to 13180 pounds. Both models had associated COVs that

ranged from below 10% to exceeding 40%, the latter reflecting the relatively large

amount of variance in the measured fracture energy and tension strength perpendicular to

grain material property values. Because both models predicted capacity as a function of

loaded edge distance, theoretical resistances increased along with loaded edge distance

for all cases. An additional trend of both models was that of higher predicted capacity

resistances for PSL connections in comparison with MSR lumber and LVL. This was

due to PSL having a significantly larger fracture energy than the two respective materials,

and both models including fracture energy as an input value.

Table 4-29: Average Fracture Lateral Connection Resistance Values at Capacity, with Associated COVs

4 7 10 4 7 10 4 7 10Average 5855 6360 6990

COV 20.7% 15.4% 16.4%Average 4677 8406 13923 6170 8935 13610 7578 11847 17581

COV 34.3% 21.3% 10.6% 10.2% 16.0% 9.2% 15.7% 10.6% 14.7%Average 5447 5931 7547

COV 40.4% 7.6% 20.8%Average 4945 7193 5215 9439 8429 13802

COV 8.6% 4.0% 14.1% 6.5% 20.9% 17.0%

4 7 10 4 7 10 4 7 10Average 6459 7331 8056

COV 20.9% 15.6% 17.2%Average 5156 7829 9988 7100 8627 9989 8760 11409 13185

COV 35.1% 21.7% 10.8% 10.3% 16.4% 8.7% 16.2% 11.4% 15.2%Average 6004 6844 8725

COV 42.7% 7.2% 22.0%Average 5365 6467 5955 9189 9699 13309

COV 9.6% 6.0% 14.5% 7.6% 21.4% 18.1%




LVL

Capacity (lb) Jensen


Span

: D

epth

Rat

io 10

5

3

0

Span

: D

epth

Rat

io 10

5

3

0

Capacity (lb) Van der Put

Loaded Edge DistanceMSR



Eurocode 5 design values were also calculated, according to Equations 2-24 and

2-25 (Table 4-30). It should be noted that the characteristic splitting equation was

adapted for softwoods, with no consideration to hardwoods or SCL. Values were

adjusted to the short-term load duration. For the connection case researched, loaded edge

distance and member depth were the only two inputs needed to calculate characteristic

splitting capacity. Therefore, design splitting capacities were only calculated for the

three loaded edge distance cases.

Table 4-30: Eurocode 5 Design Splitting Capacities

Width, in.Height, in.

Loaded Edge, in. 2 3.5 5Characteristic Splitting

Capacity, lb 1004 1572 2426

Design Splitting Capacity, lb

695 1088 1679

1.57.25

4.5.2 Comparison of Theoretical (Calculated) Values to Test Values

A summary of all C/T ratio results is provided in Appendix D. Statistical

comparisons were conducted between average set C/T ratios and associated COVs, in an

identical manner as that used to compare TR-12 model C/T ratios (Section 4.4.2).

4.5.2.1 Comparisons with Variable Span:Depth Ratios

Span:depth ratio effects were investigated by comparing average C/T ratios of

connection sets with the same main member material and loaded edge distance of 4D.

Tables 4-31 to 4-33 summarize these comparisons, for each material group of connection

sets. Van der Put model C/T ratios ranged from approximately 1.75 to 2.50, while Jensen

model C/T ratios ranged from approximately 1.95 to 3.00. For all comparison cases with

both models, no statistical difference between C/T ratios was detected across varying

span:depth ratios.


Table 4-31: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for MSR Connection Sets with Variable Span:Depth Ratio (with Detected Statistical



COV 16.4% 10.8% 22.6% COV 17.2% 11.9% 24.4%Anova p-value Anova p-value

Tukey's Conclusion

Tukey's Conclusion

MSR Connections with 4D Loaded Edge

Van der Put Set Jensen Set

0.7639 0.8032


Table 4-32: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for LVL Connection Sets with Variable Span:Depth Ratio (with Detected Statistical




Tukey's Conclusion

Tukey's Conclusion

LVL Connections with 4D Loaded Edge


0.9968 0.9951


Table 4-33: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for PSL Connection Sets with Variable Span:Depth Ratio (with Detected Statistical




Tukey's Conclusion

Tukey's Conclusion

PSL Connections with 4D Loaded Edge


0.1551 0.1634



4.5.2.2 Comparisons with Variable Loaded Edge Distance

Statistical comparisons were made comparing average C/T ratios of connection

sets with the same main member material and span:depth ratio of 5:1, in order to examine

the effect of varying loaded edge distance. Tables 4-34 to 4-36 include the average C/T

ratios, associated COVs, and statistics for each material group of connection sets.

Average C/T ratios ranged from approximately 1.75 to 2.50 for the Van der Put

model, and from 1.50 to 3.00 for the Jensen model. The Van der Put model detected a

significant trend in MSR lumber where C/T ratios increased along with loaded edge

distance, while detecting no statistical difference in C/T ratios for LVL and PSL with

respect to varying loaded edge distance. The opposite trend appeared in the Jensen

model, where the 4D loaded edge had significantly higher C/T ratios than the 10D loaded

edge, for all three material types. Explanations for these observed trends were

inconclusive, as both experimental and theoretical capacity values increased along with

loaded edge distance, which yielded little anticipation for changes in C/T ratios to be

detected.

Table 4-34: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for MSR Connection Sets with Variable Loaded Edge Distance (with Detected Statistical




Tukey's Conclusion

Tukey's Conclusion

(M-5-10) > (M-5-7) > (M-5-4) (M-5-4) > (M-5-10)

0.0001 0.0417

MSR Connections with 5:1 Span:Depth Ratio



Table 4-35: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for LVL Connection Sets with Variable Loaded Edge Distance (with Detected Statistical




Tukey's Conclusion

Tukey's Conclusion

No Difference Detected (L-5-4) > (L-5-7) > (L-5-10)

0.4860 0.0001

LVL Connections with 5:1 Span:Depth Ratio


Table 4-36: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for PSL Connection Sets with Variable Loaded Edge Distance (with Detected Statistical




Tukey's Conclusion

Tukey's Conclusion

No Difference Detected (P-5-4) > (P-5-10)

0.8990 0.0008

PSL Connections with 5:1 Span:Depth Ratio


4.5.2.3 Comparisons with Variable Material

The influence of varying main member material type was investigated by

statistically comparing C/T ratios of connection sets with the same span:depth ratio of 5:1

and loaded edge distance. Tables 4-37 through 4-39 present the average C/T ratios,

associated COVs, and statistics for connection sets grouped by loaded edge distance.

C/T ratios ranged from approximately 1.50 to 2.50 for the Van der Put model, and

from approximately 1.50 to 3.00 for the Jensen model. In all cases for both models, PSL

had average C/T ratios that were statistically higher than one or both of the other two

materials. This was presumably due to the significantly higher measured fracture energy

of PSL in comparison with values for MSR lumber and LVL, which led to higher

calculated capacities for PSL.


Table 4-37: Average Fracture C/T Ratios, Associated COVs, and Statistical Comparisons for Connection Sets with 4D Loaded Edge Distance and Variable Material Type (with




Tukey's Conclusion

Tukey's Conclusion


Van der Put Set Jensen

0.0016 0.0007

Set

PSL > MSR PSL > MSR, LVL > MSR





Tukey's Conclusion

Tukey's Conclusion


Van der Put Set Jensen

0.0210 0.0129

Set

PSL > MSR, PSL > LVL PSL > MSR, PSL > LVL





Tukey's Conclusion

Tukey's Conclusion



0.0451 0.0390

PSL > LVL PSL > LVL


4.5.2.4 Continuously Supported Subset

As with the TR-12 model, fracture C/T ratios were calculated for the continuously

supported cases(span:depth ratio of 0:1), but statistical comparisons were not conducted

due to the reduced sample size of the subset. Average C/T ratios and associated COVs,

are shown in Table 4-40 for connections with a 4D loaded edge, and Table 4-41 for

connections with a 7D loaded edge. C/T ratios at the 4D loaded edge ranged from

approximately 0.50 to 1.05 for both models, and at the 7D loaded edge from

approximately 1.00 to 1.51 for both models. Between loaded edge distance, C/T ratios

were generally higher at the 7D loaded edge distance. The observed trend in clear-span

connections of PSL having higher C/T ratios than MSR lumber and LVL was also

evident in continuously supported cases.

Table 4-40: Average Fracture C/T Ratios and Associated COVs, for Continuously Supported Connections with 4D Loaded Edge Distance


COV 25.7% 7.6% 10.9% COV 25.6% 8.1% 11.3%

Continuously Supported Connections with 4D Loaded Edge SetVan der Put Set Jensen

Table 4-41: Average Fracture C/T Ratios and Associated COVs, for Continuously Supported Connections with 7D Loaded Edge Distance


COV 5.1% 5.8% 8.6% COV 7.5% 6.6% 10.1%

Continuously Supported Connections with 7D Loaded Edge SetVan der Put Set Jensen

4.5.3 Design Value Comparison

EC5 design factors of safety (denoted as Cap/EC5), defined as the ratio of test

capacity resistance to the EC5 design splitting capacity, were calculated to relate capacity

resistance to design splitting capacity resistance. Average EC5 design factors of safety,


and associated COVs, are shown in Table 4-42. For clear-span connections, values

generally ranged from approximately 3.50 to 4.86, with no distinct trend with respect to

span:depth ratio, loaded edge distance, or material type. Continuously supported

connection values were considerably higher, ranging from approximately 5.80 to 13.75.

Loaded edge distance did appear to have an effect, as values were significantly higher at

the 4D loaded edge, in comparison with the 7D loaded edge distance.

Table 4-42: Average EC5 Design Factor of Safety Values, with associated COVs

4 7 10 4 7 10 4 7 10Average 4.71 4.22 4.86

COV 27.6% 10.8% 11.6%Average 3.78 3.82 3.54 4.03 4.10 3.97 4.33 4.43 4.26

COV 27.1% 21.6% 12.0% 7.7% 12.1% 6.5% 12.9% 8.5% 7.1%Average 4.13 3.88 4.52

COV 35.8% 6.1% 11.6%Average 13.74 5.84 12.85 8.05 13.00 8.35

COV 21.1% 5.6% 14.7% 5.5% 12.0% 8.9%

Span

: D

epth

Rat

io 10

5

3

0

MSR LVL PSLCap/EC5

Loaded Edge Distance Loaded Edge Distance Loaded Edge Distance

4.6 Comparisons Between TR-12 and Fracture Models

The relationship between the performance of the TR-12 model (at capacity

resistance), Van der Put model, and Jensen model, was analyzed by statistically

comparing the associated average C/T ratios for each connection set (shown in Sections

4.4.2 and 4.5.2). Single-factor repeated measures ANOVA was performed (α = 0.05) to

determine if a statistical difference was present between the C/T ratios of the three

models, and if so, subsequent Tukey’s HSD multiple comparisons were performed to

determine the relationship between model averages.

The results from the statistical analysis are grouped by connection material type,

in Tables 4-43 through 4-45. With five clear-span connection configurations per material

type, a total of 15 comparisons were made between the three models. In only two cases

did ANOVA fail to detect a difference between model C/T ratios, both being MSR

connection sets with a 4D loaded edge distance. In all of the remaining 13 cases, the C/T


ratios for the TR-12 model were significantly lower than Van der Put and Jensen models.

The Van der Put and Jensen models were not statistically different in 10 of the 13 cases.

For the remaining 3 cases, the Van der Put model C/T ratios were significantly higher

than the Jensen model C/T ratios.

Table 4-43: Statistical Comparisons between TR-12, Van der Put, and Jensen C/T Ratios – MSR Connections (with Detected Statistical Differences Highlighted)

Set Model Average COV Anova p-value Tukey's ConclusionTR-12 1.49 18.3%

Van der Put 1.84 16.4%Jensen 2.03 17.2%TR-12 2.08 22.4%




Van der Put 1.90 22.6%Jensen 2.09 24.4%

M-10-4

M-5-4

M-5-7

M-5-10

0.0000 (Van der Put, Jensen) > TR12

0.0000 Van der Put > Jensen > TR12


0.2702 No Difference Detected

No Difference DetectedM-3-4 0.7267

Table 4-44: Statistical Comparisons between TR-12, Van der Put, and Jensen C/T Ratios – LVL Connections (with Detected Statistical Differences Highlighted)

Set Model Average COV Anova p-value Tukey's Conclusion

TR-12 1.66 12.4%Van der Put 2.22 25.5%

Jensen 2.56 25.8%TR-12 1.64 19.7%





L-5-10 0.0000 Van der Put > Jensen > TR12

L-3-4 0.0001 (Van der Put, Jensen) > TR12



L-10-4 0.0023 Jensen > TR12


Table 4-45: Statistical Comparisons between TR-12, Van der Put, and Jensen C/T Ratios – PSL Connections (with Detected Statistical Differences Highlighted)

Set Model Average COV Anova p-value Tukey's Conclusion

TR-12 1.40 28.3%Van der Put 2.10 20.0%

Jensen 2.42 20.8%TR-12 1.46 29.6%





P-3-4 0.0013 (Van der Put, Jensen) > TR12


P-5-10 0.0000 Van der Put > Jensen > TR12



P-10-4

By the rationale described in Section 4.4.2, the lower C/T ratios of the TR-12

model equated to more accurate (or desirable if the value was less than one, in terms of

being conservative) model performance. This trend is illustrated in Figure 4-14, for all

connection sets with span:depth ratio of 5:1. As shown, at the 4D loaded edge distance,

all models had C/T ratios above one, indicating an over-prediction of connection

capacity. However while C/T ratios were relatively constant for the two fracture models,

at the 7D and 10D loaded edge distance, the TR-12 model C/T ratios tended to decrease

as loaded edge distance increased. At the 7D loaded edge distance, TR-12 C/T ratios

were approximately one, equating to relatively accurate prediction. At the 10D loaded

edge distance, TR-12 C/T ratios were consistently below one, meaning the model

conservatively predicted connection resistance. In contrast, C/T ratios from the two

fracture models generally ranged from 1.50 to 2.50, equating to the models typically

predicting capacity resistance that was 1.5 to 2.5 times larger than the actual measured

capacity resistance.


Model Comparison

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00


C/T

Rat

io

TR12 - MSRTR12 - LVLTR12 - PSLVan - MSRVan - LVLVan - PSLJensen - MSRJensen - LVLJensen - PSL

Figure 4-14: Comparison of Model C/T Ratios for Connections with 5:1 Span:Depth Ratios

With the notable difference in trends between the fracture models, and the TR-12

model illustrated by Figure 4-14, possible explanations were considered by examining

how the assumptions of each model compared with the connection behavior observed

during testing. In all cases, at the 4D loaded edge distance, splitting was the predominant

failure mode observed during testing. At 7D and 10D loaded edges, failure modes

observed were either a combination of splitting and wood crushing, or a combination of

splitting, wood crushing, and bending of the dowel. With respect to the TR-12 equations,

which only consider crushing and dowel bending as possible failure modes, the model

generally performed better (i.e. C/T ratios were lower) for connections that exhibited

some form of the behavior assumed by the model. It was logical that C/T ratios for TR-

12 were highest (model over-predicted the most) at the 4D loaded edges, where the

connections split before resistances that would have developed the assumed failure

modes. With respect to the Van der Put and Jensen fracture models, an opposite trend in

C/T ratios would have been expected when considering failure modes. Because both

models assume failure by splitting, logic entailed that model performance in terms of C/T

ratio would have been best for 4D loaded edge connections, as these cases most


exemplified the assumed failure behavior. An explanation for this discrepancy between

the observed fracture C/T trends, and the logically expected trends based upon observed

failure behavior, was not readily available within the scope of this research.


Chapter 5: Summary and Conclusions 5.1 Summary

With the focus of investigating the behavior of laterally-loaded perpendicular to

grain bolted connections in parallel strand lumber, laminated veneer lumber, and solid-

sawn lumber, the objectives of this research were as follows: 1) collect physical data on

the behavior and mechanics of beams loaded perpendicular to grain at midspan by a

bolted double-shear laterally loaded connection, with MSR lumber, LVL, and PSL

members, up to capacity; 2) quantify the accuracy of the TR-12 model equations in

predicting 5% offset load, capacity, and failure mode; and 3) quantify the accuracy of the

fracture mechanics models of Van der Put, and Jensen. A total of one-hundred-twenty

double-shear connection specimens were tested to fulfill the first objective, while five-

hundred-fifty material property specimens were tested to serve as property values

inserted into the models mentioned in the second and third objectives. Connection test

variables included main member span:depth ratio, connection loaded edge distance, and

connection main member material. A subset of continuously supported specimens was

also included as a preliminary study. The seven material property tests, with their

respective purposes, were as follows: moisture content and specific gravity to verify the

conditioning of all connection specimens; dowel bending strength and dowel bearing

strength, to be inserted into the TR-12 equations; and Mode I fracture energy, modulus of

elasticity, shear modulus, and tension perpendicular to grain strength, to be inserted into

the two fracture model equations. TR-12 theoretical resistances were calculated at 5%

offset yield and capacity, and comparisons were made using C/T ratios, and calculating

factors of safety, over-strengths, and NDS design factors of safety. Theoretical capacity

resistances were calculated from the Van der Put and Jensen fracture models, and

comparisons were made in the form of C/T ratios, and calculating EC5 design factors of

safety. Contrasts between the three models, were formed by comparing the C/T ratios of

each model.


5.2 Conclusions

The following trends have been observed, and conclusions have been drawn, from

this research project:

5.2.1 Connection Test Results

• For all three materials, splitting of the connection member was the predominant

observed failure mode at the 4D loaded edge distance, for clear-span connection

cases. Mixed modes comprised of splitting and crushing or bending of the

fastener, occurred at 7D and 10D loaded edge distances. Crushing and fastener

bending were the failure mechanisms for the continuously supported specimens.

• A significant amount of splitting occurred in all clear-span connection cases.

• At both 5% offset yield and capacity levels, span:depth ratio had a negligible

effect on resistances, while resistances increased with higher loaded edge

distances. Capacity resistances of continuously supported connections were

higher than clear-span specimens with similar loaded edge distances.

• Linear regressions between capacity and 5% offset yield resistance, for each

material, revealed relatively good correlations. For PSL, capacity was 1.69 times

5% offset yield, while for MSR and LVL, capacity was approximately 1.37 times

5% offset yield.

• Ductility ratios increased significantly with higher loaded edge distances.

5.2.2 Material Property Test Results

• When testing perpendicular to grain dowel embedment strength of MSR lumber,

and also in some instances for PSL, compaction behavior occurs that compels the

need for a displacement limit to be placed in defining capacity (Section 4.3.3).

This behavior appeared to be due to growth ring orientations in the MSR lumber,

and strand compaction in PSL.

• Measured PSL Mode I fracture energy was significantly higher than MSR lumber

and LVL values, due to the added presence of both strand boundaries and voids in

the material cross section.


• COVs from shear modulus, modulus of elasticity, dowel embedment, moisture

content, and specific gravity tests, were generally lower for LVL and PSL, than

MSR lumber.

5.2.3 Analysis of TR-12 Performance and Design Value Comparisons

• Given that failure modes observed, and that the TR-12 predicted behavior up to

capacity was crushing of the connection main member, it is particularly notable

that the predominantly observed behavior of the 4D loaded edge distance did not

include crushing of the main member. In other words, the mechanisms assumed

to occur at the minimum allowed loaded edge distance, did not develop before the

connection failed by splitting.

• Generally, span:depth ratio and material type did not have an effect on TR-12

model performance, in terms of C/T ratios. C/T ratios were lower at higher

loaded edge distances, due to test resistances that increased along with loaded

edge distance.

• Factor of safety and over-strength values were higher at higher loaded edge

distances. Material type also had a significant effect, with values highest for PSL,

followed by MSR lumber and LVL.

• Design factors of safety were typically within 20% of corresponding factors of

safety. A significant exception though was in cases where the NDS lateral design

value was controlled by the allowable shear term, which occurred in cases with

3:1 or 5:1 span:depth ratios, and 4D or 7D loaded edge distances. In these cases

the design factors of safety were quite conservative, especially for the 4D loaded

edge distance (minimum allowed by NDS).

5.2.4 Analysis of Van der Put Model and Jensen Model Performance

• Generally, span:depth ratio did not have an effect on the performance of either

fracture model, in terms of C/T ratios. C/T ratios from the Jensen model were

generally higher for smaller loaded edge distances.


• Due to the significantly higher measured fracture energy of PSL, C/T ratios

calculated from both models were highest for PSL.

• Eurocode 5 design factors of safety were not affected by any of the test variables.

5.2.5 Comparison of TR-12, Van der Put, and Jensen Models

• In 13 of 15 comparisons, TR-12 C/T ratios were significantly lower than those

calculated from the Van der Put model and the Jensen model.

• A statistical difference between the Van der Put model and the Jensen model was

detected in three cases; in all of these cases the Van der Put model had a

significantly higher C/T ratio.

• All models over-predicted connection capacity (C/T > 1.0) at the 4D loaded edge

distance. While the fracture models consistently over-predicted connection

capacity at higher loaded edge distances, the TR-12 model was reasonably

accurate (C/T ≈ 1.0) at the 7D loaded edge, and conservative (C/T < 1.0) at the

10D loaded edge.

5.2.6 Conclusions Regarding Importance of Inputs into Model Equations

• With respect to the TR-12 model, the importance of capacity embedment strength

must be noted, and specifically how it should be defined whenever the previously

mentioned compaction behavior (Section 4.3.3) occurs during testing. In this

research, this phenomenon was dealt with by using a displacement limit of 0.75

inches to define capacity if the maximum load had not been achieved prior in the

embedment test. This decision directly affected TR-12 capacity C/T ratios.

• With respect to the Van der Put model, and the Jensen model, Mode I fracture

energy was shown to be an important input, as value trends were evident in model

predictions. It must be noted that while the methods used in this research to

measure Mode I fracture energy were formulated considering several standards

and the best practices of previous researchers, a set test standard currently does

not exist to determine this property value for wood materials. With no standard in

place, and fracture energy being such a critical input into the fracture models, a


potential for inconsistency existed when attempting to measure the property

value, and then subsequently calculating theoretical connection splitting

capacities.

5.3 Limitations

The scope of this research project yielded the following limitations:

• All connections were double-shear, single-fastener configurations that were

expected to exhibit crushing of the main member behavior.

• A single fastener type was included. Connections including nails, timber rivets,

lag screws, wood screws, metal plates, etc., could have behaved differently.

• Materials tested included only southern pine MSR lumber, LVL, and PSL.

Alternate species groups and grades of solid lumber, and well as different types

structural composite lumber (laminated strand lumber, oriented strand lumber)

were not considered.

• All connection side members were steel.

• All tests were conducted under monotonic loading conditions.

5.4 Recommendations for Future Work

Investigations should be conducted to verify the trends of this research for

connection configurations with expected fastener bending yield behavior (NDS Modes III

and IV). It would specifically be of interest to investigate whether or not these modes are

permitted to develop at minimum loaded edge distances, given that this research observed

pure splitting failures at minimum loaded edge distances, before the expected member

crushing (Mode I) developed. Additionally, the allowance currently existing in the NDS

to account for splitting potential at relatively low loaded edge distances (allowable shear

design check), was found to be overly conservative in terms of design factor of safety. In

order to address this issue, it should be determined if this trend also occurs in alternate

connection configurations, as mentioned above.

Single-shear connections, and variable fastener dowel diameter, are also two

potential considerations that could be included in future work.


An investigation focusing on connection capacity resistances attained under cyclic

loading would also particularly be of value, given the growing emphasis of connection

performance under seismic and wind loads. It is notable that a vast majority of cyclic

connection studies exclusively pertain to parallel to grain orientations; the knowledge

base for perpendicular to grain orientations is not nearly as developed.

Lastly, as mentioned by Smart (2002), future research should continue to

investigate and quantify the over-strength values for a range of commonly applied

connection configurations. Such work would facilitate the principle objective of

instituting pure reliability-based design concepts into the design of lateral wood

connections.

113

References ASTM D 143-94. 2005a. Standard Test Methods for Small Clear Specimens of Timber. American Society of Testing and Materials, West Conshohocken, PA. ASTM D 198-05. 2005b. Standard Test Methods of Static Tests of Lumber in Structural Sizes. American Society of Testing and Materials, West Conshohocken, PA. ASTM E 399-90. 2005c. Standard Test Method for Plain-Strain Fracture Toughness of

Metallic Materials. American Society of Testing and Materials, West Conshohocken, PA.

ASTM F 1575-03. 2005d. Standard Test Method for Determining Bending Yield

Moment of Nails. American Society of Testing and Materials, West Conshohocken, PA.

ASTM D 2395-02. 2005e. Standard Test Methods for Specific Gravity of Wood and

Wood-Based Materials. American Society of Testing and Materials, West Conshohocken, PA.

ASTM D 4442-92. 2005f. Standard Test Methods for Direct Moisture Content

Measurement of Wood and Wood-Base Materials. American Society of Testing and Materials, West Conshohocken, PA.

ASTM D 5045-99. 2005g. Standard Test Methods for Plane-Strain Fracture Toughness

and Strain Energy Release Rate of Plastic Materials. American Society of Testing and Materials, West Conshohocken, PA.

ASTM D 5652-95. 2005h. Standard Test Methods for Bolted Connections in Wood and

Wood-Based Products. American Society of Testing and Materials, West Conshohocken, PA.

ASTM D 5764-97a. 2005i. Standard Test Method for Evaluating Dowel-Bearing Strength

of Wood and Wood-Based Products. American Society of Testing and Materials, West Conshohocken, PA.

American Forest and Paper Association (AF&PA). 1999. General Dowel Equations for

Calculating Lateral Connection Values – Technical Report 12. American Forest and Paper Association, Washington, D.C.

American Forest and Paper Association (AF&PA). 2005. National Design Specification

for Wood Construction. American Forest and Paper Association, Washington, D.C.

114

American Institute of Steel Construction (AISC). 2001. Manual of Steel Construction.

Third Edition. American Institute of Steel Construction, Inc., Chicago, IL. Albright, D.G. 2006. The Effects of Bolt Spacing on the Performance of Single-Shear Timber Connections Under Reverse-Cyclic Loading. M.S. Thesis. Virginia Polytechnic Institute and State University. Blacksburg, VA. 290 p. Aune, P. and M. Patton-Mallory. 1986. Lateral Load-Bearing Capacity of Nailed Joints

Based on the Yield Theory: Experimental Verification. Research Paper FPL 470, USDA, Forest Service, Forest Products Laboratory. Madison, WI.

Ballerini, M. 1999. A New Set of Experimental Tests on Beams Loaded Perpendicular to

Grain by Dowel Type Joints. CIB-W18 meeting thirty-two, paper 32-7-2, Graz, Austria.

Billings, M.A. 2004. Investigation of the Effects of Spacing Between Bolts in a Row in a Single-Shear Timber Connection Subjected to Reverse Cyclic Loading. M.S.

Thesis. Virginia Polytechnic Institute and State University. Blacksburg, VA. 264 p.

Bodig, J. and B.A. Jayne. 1982. Mechanics of Wood and Wood Composites. Van

Nostrand Reinhold Company, New York. 714 p. Boise EWP. 2006. Eastern Engineered Wood Products Specifier Guide. Boise Building Solutions Manufacturing, L.L.C. 36 p. Boresi, A.P., and R.J. Schmidt. 2003. Advanced Mechanics of Materials. 6th ed. John

Wiley & Sons, New York, NY. Bowyer, J.L., R. Shmulsky, J.G. Haygreen. 2003. Forest Products and Wood Science:

An Introduction. Fourth Edition. Iowa State Press. Ames, IA. Breyer, D.E., K.J. Fridley, D.G. Pollock and K.E. Cobeen. 2003. Design of Wood Structures – ASD. McGraw-Hill. New York, NY. Carstens, S.J. 1998. Bolt Bearing Behavior of Engineered Wood Composites from

Yellow Poplar Lumber. M.S. Thesis. Washington State University. Pullman, WA. 88 p.

Doyle, D.V. and J.A. Scholten. 1963. Performance of Bolted Joints in Douglas-fir. Res. Pap. FPL 2. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 10 p.

115

Ehart, R.J.A., S.E. Stanzl-Tschegg, and E.K. Tschegg. 1998. Fracture Characteristics of PARALLAM® PSL in Comparison to Solid Wood and Particleboard. Wood Science and Technology. 32: 43-55.

Ehlbeck, J, R. Gorlacher, and H. Werner. 1989. Determination of Perpendicular to Grain Tensile Stresses in Joints with Dowel-Type Fasteners – a Draft Proposal for

Design Rules. CIB-W18 meeting twenty-two, paper 22-7-2, Berlin, Germany. ENV 2005-1-1 Eurocode 5. 2004. Design of Timber Structures, Part 1. Comite

Europeen de Normalisation, Brussels, Belgium Foschi, R.O., B.R. Folz, and F.Z. Yao. 1989. Reliability-Based Design of Wood

Structures, Structural Research Series, Report No. 34, Department of Civil Engineering, University of British Columbia, Vancouver, Canada.

Goodell, H.R. and R.S. Phillips. 1944. Bolt-Bearing Strength of Wood and Modified

Wood: Effects of Different Methods of Drilling Bolt Holes in Wood and Plywood. Report No. 1523, USDA Forest Service, Forest Products Laboratory, Madison, WI.

Green, D.W. and D.E. Kretschmann. 1994. Moisture Content and the Properties of Clear Southern Pine. USDA Forest Products Laboratory. Research paper FPL-RP-531 Gutshall, S.T. 1994. Monotonic and Cyclic Short-Term Performance of Nailed and

Bolted Timber Connections. M.S. Thesis. Virginia Polytechnic Institute and State University. Blacksburg, VA. 192 p.

Harrison, S.K. 2006. Comparison of Shear Modulus Test Methods. M.S. Thesis. Virginia Polytechnic Institute and State University. Blacksburg, VA. 106 p. Heine, C.P. 2001. Simulated Response of Degrading Hysteretic Joints with Slack

Behavior. Ph.D. dissertation. Virginia Polytechnic Institute and State University. Blacksburg, VA. 292 p.

Hummer, T., J.D. Dolan, and M. Wolcott. 2006. Tension Perpendicular to Grain Strength

of Wood, Laminated Veneer Lumber, and a Wood Plastic Composite. Proceedings of the World Conference on Timber Engineering, Portland, Oregon, USA. August 6-10, 2006, 6 p.

iLevel. 2006. Trus Joist Beam, Header, and Column Specifier’s Guide TJ-9000. iLevel by Weyerhaeuser, Boise, ID. 41 p.

Janowiak, J.J., D.P. Hindman, and H.B. Manbeck. 2001. Orthotropic Behavior of Lumber Composite Material. Wood and Fiber Science. 33(4): 580-594.

116

Jensen, J.L, P.J. Gustafsson, and H.J. Larsen. 2003. A Tensile Fracture Model for Joints with Rods or Dowels Loaded Perpendicular to Grain. CIB-W18 meeting thirty-six, paper 36-7-9, Colorado, USA.

Jensen, J.L. 2003. Splitting Strength of Beams Loaded by Connections. CIB-W18

meeting thirty-six, paper 36-7-8, Colorado, USA. Jensen, J.L. 2005. Quasi-non-linear Fracture Mechanics Analysis of the Splitting Failure

of Single Dowel Joints Loaded Perpendicular to grain. Journal of Wood Science. 51:6. p. 559-565.

Johnson, E. and F. Woeste. 2000. Connection Design Methodology for Structural

Composite Lumber. Research Report. Department of Wood Science and Forest Products, Virginia Polytechnic Institute and State University. Blacksburg, VA. 15 p.

Jorissen, A. 1998. Double Shear Timber Connections with Dowel Type Fasteners. PhD

Dissertation, Delft University of Technology, Delft, The Netherlands. Kasim, M. and J.H.P. Quenneville. 2002. Effect of Row Spacing on the Capacity of

Perpendicular to Grain Loaded Timber Joints with Multiple Timber Connections Loaded Perpendicular to Grain. CIB-W18 meeting thirty-five, paper 35-7-6,

Kyoto, Japan. Köhler, J., A. Leijten, and A. Jorissen. 2006. Uncertainties Related to the Strength

Modeling of Dowel Type Fastener Connections. Proceedings of the World Conference on Timber Engineering, Portland, Oregon, USA. August 6-10, 2006, 9 p.

Line, P. 2007. Manager, Engineering Research, American Forest & Paper Association.

Electronic mail correspondence. May, 2007. McLain, T.E. and S. Thangjitham. 1983. Bolted Wood-Joint Yield Model. Journal of

Structural Engineering, ASCE. 109(8): 1820-1835. Petterson, H. 1995. Fracture Mechanics of Timber Beams and End Notches. CIB-W18

meeting twenty-eight, paper 28-19-3, København, Danmark Petterson, R.W., J. Bodig, F.W. Smith. 1981. Prediction of Mode I TL Fracture

Toughness for Conifers. Structural Research Report No. 39, Civil Engineering Department, Colorado State University, Ft. Collins, Colorado.

Quenneville, J.H.P, and M. Mohammad. 2001. A Proposed Canadian Design Approach

for Bolted Connections Loaded Perpendicular to Grain. Joints in Timber Structures, Proceedings of the International RILEM Symposium, Stuttgart, Germany.

117

Rammer, D.R. and S.G. Winistorfer. 2001. Effect of Moisture Content on Dowel-Bearing

Strength. Wood and Fiber Science. 33(1): 126-139. Ramskill, T.E. 2002. Effect of Cracking on Lag Bolt Performance. Ph.D. dissertation. Virginia Polytechnic Institute and State University. Blacksburg, VA. 306 p. Reffold, A., T.N. Reynolds, and B.S. Choo. 1999. An Investigation into the Tensile Strength of Nail Plate Timber Joints Loaded Perpendicular to the Grain. Journal of the Institute of Wood Science. 15(1). Reshke, R.G. 1999. Bolted Timber Connections Loaded Perpendicular-to-Grain. Ph.D. dissertation. Royal Military College of Canada. Kingston, Ontario. 294 p. Reshke, R.G., M. Mohammad and J.H.P. Quenneville. 2000. Influence of Joint

Configuration Parameters on Strength of Perpendicular to Grain Bolted Timber Connections. 6th World Conference on Timber Engineering, Whistler, British Columbia, Canada.

Rosowsky, D., D.S. Gromala, and P. Line. 2005. Reliability-Based Code Calibration for

Design of Wood Members Using Load and Resistance Factor Design. Journal of Structural Engineering, ASCE, 131(2): 338-344.

Schoenmakers, J.C.M. 2006. PhD Candidate, Delft University of Technology, Delft, The

Netherlands. Electronic mail correspondence. August, 2006. Smart, J.V. 2002. Capacity Resistance and Performance of Single-Shear Bolted and

Nailed Connections: an Experimental Investigation. M.S. Thesis. Virginia Polytechnic Institute and State University. Blacksburg, VA. 131 p.

Smith, I., and G. Foliente. 2002. Load and Resistance Factor Design of Timber Joints:

International Practice and Future Direction, Journal of Structural Engineering, ASCE, 128(1): 48-59.

Smith, I., E. Landis, and M. Gong. 2003. Fracture and Fatigue in Wood. John Wiley & Sons Ltd. Sussex, England. 234 p. Smulski, S. 1997. Engineered Wood Products, a Guide for Specifiers, Designers, and

Users. PFS Research Foundation. Madison, WI. 294 p. Snow, M., A. Asiz, and I. Smith. 2004a. Failure Behaviour of Single Dowel Connections

in Engineered Wood Products. 5th Structural Specialty Conference of the Canadian Society for Civil Engineering. Saskatoon, Saskatchewan, Canada. 9 p.

118

Snow, M., I. Smith, and A. Asiz. 2004b. Dowel Joints in Engineered Wood Products: Assessment of Simple Fracture Mechanics Models. CIB-W18 meeting thirty-seven, paper 37-7-15, Edinburgh, Scotland. 12 p.

Soltis, L.A.; Hubbard, F.K.; and T.L. Wilkinson. 1986. Bearing Strength of Bolted

Timber Joints. Journal of Structural Engineering, ASCE. 112(9): 2141-2154. Soltis, L.A., S. Karnasuirdja, J.K. Little. 1987. Angle to Grain Strength of Dowel-Type

Fasteners. Wood and Fiber Science. 19(1): 68-80. Soltis, L.A. and T.L. Wilkinson. 1987. Bolted Connection Design. General Technical

Report FPL-GTR-54, USDA, Forest Service, Forest Products Laboratory, Madison, WI.

Stanzl-Tschegg, S.E., D.M. Tan, and E.K. Tschegg. 1995. New Splitting Method for Wood Fracture Characterization. Wood Science and Technology. 29: 31-50. Trayer, G.W. 1932. The Bearing Strength of Wood Under bolts. Technical Bulletin No.

332. USDA. Washington, D.C. Van der Put, T.A.C.M. 1990. Tension Perpendicular to Grain at Notches and Joints.

CIB-W18 meeting twenty-three, paper 23-10-1, Lisbon, Portugal. Van der Put, T.A.C.M. and A.J.M. Leijten. 2000. Evaluation of Perpendicular to Grain

Failure of Beams Caused by Concentrated Loads at Joints. CIB-W18 meeting thirty-three, paper 33-7-7, Delft, The Netherlands.

Wilkinson, T.L. 1991. Dowel Bearing Strength. Research Paper FPL-RP-505, USDA

Forest Service, Forest Products Laboratory, Madison, WI. Wilkinson, T.L. 1993. Bolted Connection Strength and Bolt Hole Size. Research Paper

FPL-RP-524, USDA Forest Service, Forest Products Laboratory, Madison, WI. Williams, G.C. 1999. Engineered Wood Products – Experience and Opportunities.

Proceedings of Timber Engineering Conference. Rotorua, New Zealand. Yasumura, M. 2001. Criteria for Damage and Failure of Dowel-Type Joints Subjected

to Force Perpendicular to Grain. CIB-W18 meeting thirty-four, paper 34-7-9, Venice, Italy.

Appendix A 119

Appendix A - Connection Test Load-Displacement Curves

Set M-5-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

M-5-4-1M-5-4-2M-5-4-3M-5-4-4M-5-4-5M-5-4-6Average

Set M-10-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

M-10-4-1M-10-4-2M-10-4-3M-10-4-4M-10-4-5M-10-4-6AverageM-10-4-7M-10-4-8M-10-4-9M-10-4-10

Appendix A 120

Set M-5-7

0

1000

2000

3000

4000

5000

6000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

M-5-7-1M-5-7-2M-5-7-3M-5-7-4M-5-7-5M-5-7-6Average

Set M-5-10

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

M-5-10-1M-5-10-2M-5-10-3M-5-10-4M-5-10-5M-5-10-6Average

Appendix A 121

NOTE: Data acquisition error occurred for Specimen M-0-4-3 - Trial omitted

Set M-3-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

M-3-4-1M-3-4-2M-3-4-3M-3-4-4M-3-4-5M-3-4-6Average

Set M-0-4

0

2000

4000

6000

8000

10000

12000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

M-0-4-1M-0-4-2

Appendix A 122

Set M-0-7

0

2000

4000

6000

8000

10000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

M-0-7-1M-0-7-2M-0-7-3

Appendix A 123

Set L-5-4

0

1000

2000

3000

4000

5000

0.0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

L-5-4-1L-5-4-2L-5-4-3L-5-4-4L-5-4-5L-5-4-6Average

Set L-10-4

0

1000

2000

3000

4000

5000

0.0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

L-10-4-1

L-10-4-2

L-10-4-3

L-10-4-4

L-10-4-5

L-10-4-6

L-10-4-7

L-10-4-8

L-10-4-9

L-10-4-10

Average

Appendix A 124

Set L-5-7

0

1000

2000

3000

4000

5000

6000

0.0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

L-5-7-1L-5-7-2L-5-7-3L-5-7-4L-5-7-5L-5-7-6Average

Set L-5-10

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0.0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

L-5-10-1L-5-10-2L-5-10-3L-5-10-4L-5-10-5L-5-10-6Average

Appendix A 125

Set L-3-4

0

1000

2000

3000

4000

5000

0.0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

L-3-4-1L-3-4-2L-3-4-3L-3-4-4L-3-4-5L-3-4-6Average

Set L-0-4

0

2000

4000

6000

8000

10000

12000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

L-0-4-1L-0-4-2L-0-4-3

Appendix A 126

Set L-0-7

0

2000

4000

6000

8000

10000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

L-0-7-1L-0-7-2L-0-7-3

Appendix A 127

Set P-5-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

P-5-4-1P-5-4-2P-5-4-3P-5-4-4P-5-4-5P-5-4-6Average

Set P-10-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

P-10-4-3P-10-4-4P-10-4-5P-10-4-6P-10-4-7P-10-4-8AverageP-10-4-9P-10-4-10P-10-4-11P-10-4-12

Appendix A 128

Set P-5-7

0

1000

2000

3000

4000

5000

6000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

P-5-7-1P-5-7-2P-5-7-3P-5-7-4P-5-7-5P-5-7-6Average

Set P-5-10

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

Slip (in)

Res

ista

nce

(lb)

P-5-10-1P-5-10-2P-5-10-3P-5-10-4P-5-10-5P-5-10-6Average

Appendix A 129

Set P-3-4

0

1000

2000

3000

4000

5000

0 0.2 0.4 0.6

Slip (in)

Res

ista

nce

(lb)

P-3-4-1P-3-4-2P-3-4-3P-3-4-4P-3-4-5P-3-4-6Average

Set P-0-4

0

2000

4000

6000

8000

10000

12000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

P-0-4-1P-0-4-2P-0-4-3

Appendix A 130

Set P-0-7

0

2000

4000

6000

8000

10000

0 0.2 0.4 0.6 0.8

Slip (in)

Res

ista

nce

(lb)

P-0-7-1P-0-7-2P-0-7-3

Appendix B 131

Appendix B - Connection Test Data

Set: M-10-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-10-4-1 2837 0.0737 3211 0.1028 68031 1.39 S 21.72M-10-4-2 2193 0.0865 2434 0.1345 34334 1.55 S 16.84M-10-4-3 1855 0.0614 1972 0.0720 58589 1.17 S 17.84M-10-4-4 3666 0.0697 4184 0.1005 90909 1.44 S 22.94M-10-4-5 3026 0.0777 3541 0.1403 57849 1.81 S 23.97M-10-4-6 3251 0.0568 4143 0.1149 137924 2.02 S 21.59M-10-4-7 1802 0.0656 2113 0.1207 47461 1.84 S 21.34M-10-4-8 3696 0.0764 4668 0.1412 95060 1.85 S 15.06M-10-4-9 2640 0.0829 3169 0.1384 51897 1.67 S 23.94

M-10-4-10 2872 0.0714 3334 0.1082 70574 1.52 S 22.22

Average 2784 0.0722 3277 0.1174 71263 1.63 20.75St. Dev 674 0.0093 905 0.0223 29912 0.26 3.08COV 24.2% 12.8% 27.6% 19.0% 42.0% 15.8% 14.9%

Set: M-5-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-5-4-1 1525 0.0753 1725 0.1033 27898 1.37 S 8.03M-5-4-2 1958 0.0627 2419 0.1279 48469 2.04 S 2.53M-5-4-3 2822 0.0681 3469 0.1321 74173 1.94 S 4.56M-5-4-4 1725 0.0784 2124 0.1368 33264 1.74 S 5.06M-5-4-5 2771 0.0698 3470 0.1477 63045 2.12 Im-S 10.53M-5-4-6 1998 0.0843 2537 0.2213 41370 2.63 Im-S 7.09


Set: M-5-7

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-5-7-1 3881 0.1190 5016 0.1891 46081 1.59 Im-S 22.13M-5-7-2 1830 0.0779 2985 0.3613 40948 4.64 Im-S 19.25M-5-7-3 3347 0.0902 4086 0.1459 54086 1.62 Im-S 19.91M-5-7-4 2323 0.0865 3175 0.2366 43001 2.74 Im-S 10.00M-5-7-5 3759 0.0858 4664 0.1993 68706 2.32 Im-S 22.13M-5-7-6 2825 0.0893 4993 0.2946 52315 3.30 Im-S 20.22


Specimen5% Offset Yield Capacity Stiffness

(lb/in)Ductility

Ratio Failure Mode Crack (in)


(lb/in)Ductility


Ductility Ratio Failure Mode Crack (in)Specimen

5% Offset Yield Capacity Stiffness (lb/in)

Appendix B 132

Set: M-5-10

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-5-10-1 3420 0.0845 5685 0.2981 67603 3.53 Im-S 12.06M-5-10-2 3316 0.1048 5845 0.4723 51163 4.51 Im-S 20.53M-5-10-3 3052 0.1047 5480 0.4311 47296 4.12 Im-S 22.13M-5-10-4 3295 0.0878 5144 0.3647 58528 4.15 Im-S 18.84M-5-10-5 3745 0.0749 7143 0.3519 67573 4.70 IIIs-S 20.72M-5-10-6 3072 0.0834 6338 0.5480 62210 6.57 Im-S 19.66


Set: M-3-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-3-4-1 1458 0.0624 1822 0.1081 37998 1.73 S 3.56M-3-4-2 2833 0.0596 3838 0.1615 86406 2.71 Im-S 4.44M-3-4-3 3237 0.0721 4383 0.1594 75479 2.21 S 3.72M-3-4-4 2481 0.0452 2481 0.0452 76056 1.00 S 4.31M-3-4-5 1644 0.0545 1976 0.0933 54410 1.71 S 3.44M-3-4-6 1654 0.0691 2732 0.2133 40536 3.09 S 4.72


Set: M-0-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)M-0-4-1 2825 0.0706 8125 0.6642 61345 9.41 IIIs 0.00

M-0-4-21 2351 0.0621 10980 0.7500 60839 12.08 IIIs 0.00

M-0-4-32 Error Error Error Error Error Error Error Error


1 Test stopped at deflection limit (slip = 0.75")2 Data Acquisition error; test specimen omitted



Ductility Ratio Failure Mode Crack (in)


(lb/in)Ductility



(lb/in)

Appendix B 133

Set: M-0-7

Resistance (lb) Disp (in) Resistance (lb) Disp (in)

M-0-7-11 2605 0.0796 6209 0.7500 50896 9.42 IIIs 0.00

M-0-7-21 1949 0.0594 6766 0.7500 64805 12.63 IIIs 0.00

M-0-7-31 2053 0.0583 6101 0.7500 52919 12.86 IIIs 0.00


1 Test stopped at deflection limit (slip = 0.75")

Set: L-10-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)L-10-4-1 2631 0.0918 2703 0.1645 43331 1.79 S 12.38L-10-4-2 3182 0.1009 3373 0.1571 42184 1.56 S 14.16L-10-4-3 2693 0.0926 3017 0.1403 42058 1.52 S 9.84L-10-4-4 2482 0.1089 2522 0.1554 31498 1.43 S 12.84L-10-4-5 2830 0.0863 2956 0.1098 46795 1.27 S 11.63L-10-4-6 2354 0.0875 2458 0.1205 43126 1.38 S 9.66L-10-4-7 2623 0.0957 2731 0.1825 39081 1.91 S 12.38L-10-4-8 2567 0.0947 3177 0.2141 41428 2.26 S 13.78L-10-4-9 2973 0.0851 3142 0.1048 49909 1.23 S 7.72L-10-4-10 3264 0.0895 3272 0.0910 56437 1.02 S 12.81


Set: L-5-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)L-5-4-1 2668 0.1127 2693 0.1175 30810 1.04 S 9.44L-5-4-2 2474 0.0848 2567 0.1053 43167 1.24 S 5.50L-5-4-3 2639 0.0714 3153 0.1377 63913 1.93 S 6.41L-5-4-4 2484 0.0850 2636 0.1294 39137 1.52 S 8.41L-5-4-5 2419 0.0741 2864 0.1166 55541 1.57 S 7.88L-5-4-6 2394 0.0629 2912 0.2454 65275 3.90 S 10.31





(lb/in)Ductility



(lb/in)Ductility


Appendix B 134

Set: L-5-7

Resistance (lb) Disp (in) Resistance (lb) Disp (in)L-5-7-1 2737 0.0968 4068 0.2903 43758 3.00 S 12.84L-5-7-2 3507 0.1148 5174 0.2635 45093 2.30 S 9.44L-5-7-3 3053 0.0890 4433 0.2641 56384 2.97 Im-S 9.53L-5-7-4 3605 0.1285 4060 0.2370 39620 1.84 Im-S 14.47L-5-7-5 3348 0.1275 3957 0.2185 38375 1.71 S 12.41L-5-7-6 3388 0.1047 5081 0.2732 49171 2.61 Im-S 17.19


Set: L-5-10

Resistance (lb) Disp (in) Resistance (lb) Disp (in)L-5-10-1 3897 0.0948 6972 0.4283 57046 4.52 IIIs-S 14.66L-5-10-2 3397 0.0984 7034 0.4723 55099 4.80 IIIs-S 15.19L-5-10-3 3516 0.1075 7069 0.5012 48820 4.66 IIIs-S 10.28L-5-10-4 3450 0.1086 5961 0.4778 44774 4.40 IIIs-S 12.50L-5-10-5 3825 0.1175 6449 0.3965 45423 3.37 IIIs-S 14.72L-5-10-6 3205 0.1107 6546 0.5545 37862 5.01 IIIs-S 19.75


Set: L-3-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)L-3-4-1 2741 0.0903 2820 0.1043 39485 1.16 S 4.69L-3-4-2 2579 0.0841 2866 0.1145 42634 1.36 S 6.53L-3-4-3 2123 0.0849 2574 0.1681 32684 1.98 S 11.94L-3-4-4 2546 0.0722 2858 0.1031 51870 1.43 S 9.66L-3-4-5 2343 0.0799 2578 0.1141 42731 1.43 S 9.13L-3-4-6 2269 0.0703 2501 0.1312 50294 1.87 S 13.50





(lb/in)Ductility



(lb/in)Ductility


Appendix B 135

Set: L-0-4


L-0-4-11 3506 0.0774 9636 0.7500 68639 9.69 IIIs 0.00

L-0-4-21 3301 0.0817 7415 0.7500 57327 9.18 IIIs 0.00

L-0-4-31 3692 0.0953 9745 0.7500 55307 7.87 IIIs 0.00



Set: L-0-7


L-0-7-11 3782 0.0853 8318 0.7500 60560 8.79 IIIs 0.00

L-0-7-21 4009 0.0960 9279 0.7500 63670 7.81 IIIs 0.00

L-0-7-31 3499 0.0891 8676 0.7500 54695 8.42 IIIs 0.00



Set: P-10-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)P-10-4-3 2713 0.0883 3368 0.3363 41232 3.81 S 15.72P-10-4-4 1958 0.0678 3231 0.4246 47667 6.26 S 14.16P-10-4-5 2061 0.0679 3138 0.2062 44990 3.04 S 10.34P-10-4-6 2758 0.0676 3665 0.1613 68618 2.39 S 8.63P-10-4-7 2155 0.0695 2759 0.1932 49680 2.78 S 10.13P-10-4-8 2634 0.0969 3985 0.3384 42746 3.49 S 10.25P-10-4-9 2364 0.0572 3317 0.1429 81317 2.50 S 9.50P-10-4-10 3101 0.0714 3961 0.2712 71620 3.80 S 11.59P-10-4-11 1984 0.0753 3015 0.1862 36951 2.47 S 9.59P-10-4-12 2327 0.0607 3337 0.1788 71254 2.95 S 9.88








Appendix B 136

Set: P-5-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)P-5-4-1 1828 0.0740 3106 0.2967 35731 4.01 S 10.53P-5-4-2 1985 0.0832 2945 0.1733 32348 2.08 S 12.09P-5-4-3 2065 0.0686 2437 0.1370 42286 2.00 S 8.44P-5-4-4 2025 0.0629 2747 0.1387 46079 2.21 S 12.25P-5-4-5 2822 0.0848 3527 0.2073 44365 2.44 Im-S 10.31P-5-4-6 1846 0.0760 3285 0.3658 35363 4.81 S 9.03


Set: P-5-7

Resistance (lb) Disp (in) Resistance (lb) Disp (in)P-5-7-1 2370 0.1193 4303 0.4972 28531 4.17 Im-S 13.31P-5-7-2 2683 0.0747 5281 0.4620 54890 6.18 Im-S 15.97P-5-7-3 2505 0.0965 4773 0.3283 38176 3.40 Im-S 10.59P-5-7-4 2490 0.0968 4368 0.3433 35429 3.55 Im-S 14.84P-5-7-5 2944 0.1048 5079 0.3411 40189 3.25 Im-S 14.09P-5-7-6 3267 0.1217 5128 0.2988 33873 2.46 Im-S 9.25


Set: P-5-10

Resistance (lb) Disp (in) Resistance (lb) Disp (in)P-5-10-1 3092 0.1158 7188 0.5930 34853 5.12 Im-S 13.03P-5-10-2 3545 0.1191 7412 0.5867 40608 4.93 IIIs-S 9.19P-5-10-3 2977 0.1297 6930 0.5946 31244 4.58 Im-S 18.28

P-5-10-41 2005 0.1046 6399 0.7389 22971 7.06 Im-S 13.19

P-5-10-51 3593 0.1111 7923 0.7485 44058 6.74 IIIs-S 16.78P-5-10-6 3280 0.1101 7023 0.6729 41219 6.11 IIIs-S 12.56


1 Test stopped approximately at deflection limit (slip = 0.75")

Ductility Ratio Failure Mode Crack (in)


(lb/in)Ductility



(lb/in)



Appendix B 137

Set: P-3-4

Resistance (lb) Disp (in) Resistance (lb) Disp (in)P-3-4-1 1981 0.0825 3379 0.2822 37526 3.42 Im-S 6.06P-3-4-2 2243 0.0932 3171 0.2895 40120 3.11 Im-S 7.19P-3-4-3 2080 0.0807 2566 0.3027 41059 3.75 Im-S 8.44P-3-4-4 2235 0.0840 3241 0.3314 36239 3.95 S 10.53P-3-4-5 3278 0.0921 3600 0.1193 49274 1.30 S 9.59P-3-4-6 2240 0.0897 2910 0.4007 33847 4.47 Im-S 10.22


Set: P-0-4


P-0-4-11 2399 0.0603 10176 0.7500 72415 12.44 IIIs 0.00

P-0-4-21 2784 0.0778 8898 0.7500 54602 9.64 IIIs 0.00

P-0-4-31 2239 0.0989 8026 0.7500 34365 7.58 IIIs 0.00



Set: P-0-7


P-0-7-11 2966 0.0872 9221 0.7500 46517 8.60 IIIs 0.00

P-0-7-21 3007 0.0776 8224 0.7500 56664 9.66 IIIs 0.00

P-0-7-31 3287 0.0925 9824 0.7500 54608 8.11 IIIs 0.00






(lb/in)Ductility



(lb/in)Ductility


Appendix C - TR 12 Calculations (with Inputs)

Set: M-10-4Bolt

M-10-4-1 10.8% 0.58 1.515 4411 0.500 139200 72160 3341 Im 2837 1.18M-10-4-2 11.0% 0.51 1.512 2706 0.500 139200 72160 2046 Im 2193 0.93M-10-4-3 10.4% 0.43 1.510 2332 0.500 139200 72160 1761 Im 1855 0.95M-10-4-4 11.6% 0.67 1.513 4639 0.500 139200 72160 3509 Im 3666 0.96M-10-4-5 11.7% 0.58 1.518 4034 0.500 139200 72160 3062 Im 3026 1.01M-10-4-6 9.9% 0.65 1.521 4858 0.500 139200 72160 3695 Im 3251 1.14M-10-4-7 11.2% 0.45 1.502 2723 0.500 139200 72160 2045 Im 1802 1.13M-10-4-8 10.1% 0.69 1.513 6569 0.500 139200 72160 4969 Im 3696 1.34M-10-4-9 12.4% 0.57 1.516 3071 0.500 139200 72160 2328 Im 2640 0.88M-10-4-10 10.5% 0.59 1.515 4653 0.500 139200 72160 3525 Im 2872 1.23

Average 11.0% 0.57 1.513 4000 0.500 139200 72160 3028 2784 1.08St. Dev 0.8% 0.09 0.005 1303 0.000 0 0 990 674 0.15COV 7.2% 15.3% 0.3% 32.6% 0.0% 0.0% 0.0% 32.7% 24.2% 14.0%

M-10-4-1 10.8% 0.58 1.515 6471 0.500 139200 85570 4902 Im 3211 S 1.53M-10-4-2 11.0% 0.51 1.512 3771 0.500 139200 85570 2851 Im 2434 S 1.17M-10-4-3 10.4% 0.43 1.510 4580 0.500 139200 85570 3458 Im 1972 S 1.75M-10-4-4 11.6% 0.67 1.513 6609 0.500 139200 85570 5000 Im 4184 S 1.20M-10-4-5 11.7% 0.58 1.518 6569 0.500 139200 85570 4986 Im 3541 S 1.41M-10-4-6 9.9% 0.65 1.521 7320 0.500 139200 85570 5567 Im 4143 S 1.34M-10-4-7 11.2% 0.45 1.502 3875 0.500 139200 85570 2910 Im 2113 S 1.38M-10-4-8 10.1% 0.69 1.513 11984 0.500 139200 85570 9066 Im 4668 S 1.94M-10-4-9 12.4% 0.57 1.516 5578 0.500 139200 85570 4228 Im 3169 S 1.33M-10-4-10 10.5% 0.59 1.515 8211 0.500 139200 85570 6220 Im 3334 S 1.87


Specific Gravity

Bearing Length per Side (in)

Embedment Strength (psi)

Bearing Length (in)


Yield Mode

Cap

acity

Test Resistance (lb) Yield Mode

Resistance

5% O

ffse

t Yie

ld

Connection Test ResultCalc / TestMoisture

Content

Appendix C138

Note: Embedment strength of steel side members was calculated according to equation (J3-2a) from section 16.1 of the AISC Manual of Steel Construction (AISC 2001), with steel design bearing strength = ΦRn, where Rn = 2.4dtFu and Φ=0.75. Fu for A36 grade steel was 58000 psi. This was allowable according to NDS Section 10.2.3, which states that metal materials should be designed in "accordance with applicable metal design procedures". (AF&PA 2005)

Bending Strength (psi)

Lateral Resistance (lb)

Specimen Number

Main Member Side Members (steel) TR-12 Calculated Value

Set: M-5-4Bolt

M-5-4-1 13.2% 0.47 1.495 2200 0.500 139200 72160 1645 Im 1525 1.08M-5-4-2 13.5% 0.53 1.511 2279 0.500 139200 72160 1722 Im 1958 0.88M-5-4-3 11.8% 0.67 1.506 5016 0.500 139200 72160 3777 Im 2822 1.34M-5-4-4 14.1% 0.54 1.503 2077 0.500 139200 72160 1561 Im 1725 0.90M-5-4-5 11.8% 0.56 1.536 3120 0.500 139200 72160 2396 Im 2771 0.86M-5-4-6 11.4% 0.42 1.522 2779 0.500 139200 72160 2115 Im 1998 1.06Average 12.6% 0.53 1.512 2912 0.500 139200 72160 2203 2133 1.02St. Dev 1.1% 0.08 0.015 1104 0.000 0 0 834 542 0.18COV 8.5% 15.6% 1.0% 37.9% 0.0% 0.0% 0.0% 37.9% 25.4% 17.7%

M-5-4-1 13.2% 0.47 1.495 5855 0.500 139200 85570 4377 Im 1725 S 2.54M-5-4-2 13.5% 0.53 1.511 5039 0.500 139200 85570 3807 Im 2419 S 1.57M-5-4-3 11.8% 0.67 1.506 10217 0.500 139200 85570 7693 Im 3469 S 2.22M-5-4-4 14.1% 0.54 1.503 7354 0.500 139200 85570 5527 Im 2124 S 2.60M-5-4-5 11.8% 0.56 1.536 9149 0.500 139200 85570 7026 Im 3470 Im-S 2.02M-5-4-6 11.4% 0.42 1.522 5028 0.500 139200 85570 3826 Im 2537 Im-S 1.51Average 12.6% 0.53 1.512 7107 0.500 139200 85570 5376 2624 2.08St. Dev 1.1% 0.08 0.015 2194 0.000 0 0 1672 712 0.47COV 8.5% 15.6% 1.0% 30.9% 0.0% 0.0% 0.0% 31.1% 27.1% 22.4%

Set: M-5-7Bolt


M-5-7-1 13.2% 0.61 1.527 7863 0.500 139200 85570 6003 Im 5016 Im-S 1.20M-5-7-2 11.7% 0.43 1.545 4654 0.500 139200 85570 3595 Im 2985 Im-S 1.20M-5-7-3 11.7% 0.58 1.518 6916 0.500 139200 85570 5249 Im 4086 Im-S 1.28M-5-7-4 11.7% 0.52 1.505 5031 0.500 139200 85570 3786 Im 3175 Im-S 1.19M-5-7-5 10.5% 0.64 1.516 8273 0.500 139200 85570 6271 Im 4664 Im-S 1.34M-5-7-6 11.8% 0.61 1.532 6489 0.500 139200 85570 4971 Im 4993 Im-S 1.00Average 11.8% 0.57 1.524 6538 0.500 139200 85570 4979 4153 1.20St. Dev 0.9% 0.08 0.014 1465 0.000 0 0 1107 899 0.12COV 7.3% 14.0% 0.9% 22.4% 0.0% 0.0% 0.0% 22.2% 21.6% 9.8%

Main MemberBending Strength

(psi)

5% O

ffse

t Yie

ldC

apac

ity


Yield Mode Test Resistance (lb) Yield

ModeResistance Specimen

Number Bearing Length (in)




Appendix CConnection Test Result

Calc / TestMoisture Content

Specific Gravity





Main Member


Resistance

5% O

ffse

t Yie

ld

Specimen Number

Side Members (steel) TR-12 Calculated ValueYield Mode

Bearing Length (in)


139

Cap

acity

Side Members (steel) TR-12 Calculated Value Connection Test ResultCalc / TestMoisture

ContentSpecific Gravity

Set: M-5-10Bolt


M-5-10-1 11.0% 0.60 1.521 6881 0.500 139200 85570 5233 Im 5685 Im-S 0.92M-5-10-2 10.2% 0.52 1.506 5119 0.500 139200 85570 3855 Im 5845 Im-S 0.66M-5-10-3 10.9% 0.48 1.511 3809 0.500 139200 85570 2878 Im 5480 Im-S 0.53M-5-10-4 14.1% 0.60 1.505 5226 0.500 139200 85570 3933 Im 5144 Im-S 0.76M-5-10-5 11.5% 0.62 1.521 8029 0.500 139200 85570 6106 Im 7143 Im-S 0.85M-5-10-6 12.6% 0.59 1.502 6013 0.500 139200 85570 4516 Im 6338 Im-S 0.71Average 11.7% 0.57 1.511 5846 0.500 139200 85570 4420 5939 0.74St. Dev 1.4% 0.05 0.008 1478 0.000 0 0 1136 711 0.14COV 11.8% 9.3% 0.6% 25.3% 0.0% 0.0% 0.0% 25.7% 12.0% 19.1%

Set: M-3-4Bolt


M-3-4-1 12.3% 0.48 1.490 4192 0.500 139200 85570 3123 Im 1822 S 1.71M-3-4-2 13.0% 0.57 1.511 9689 0.500 139200 85570 7320 Im 3838 Im-S 1.91M-3-4-3 12.9% 0.64 1.504 11651 0.500 139200 85570 8762 Im 4383 S 2.00M-3-4-4 11.6% 0.62 1.529 7609 0.500 139200 85570 5817 Im 2481 S 2.34M-3-4-5 13.2% 0.52 1.504 6608 0.500 139200 85570 6608 Im 1976 S 3.34M-3-4-6 12.9% 0.39 1.513 5535 0.500 139200 85570 4187 Im 2732 S 1.53Average 12.6% 0.54 1.508 7547 0.500 139200 85570 5970 2872 2.14St. Dev 0.6% 0.09 0.013 2743 0.000 0 0 2066 1029 0.65COV 4.8% 17.1% 0.8% 36.3% 0.0% 0.0% 0.0% 34.6% 35.8% 30.4%

Calc / TestBending Strength (psi)




Cap

acity


Resistance

5% O

ffse

t Yie

ld

Connection Test ResultLateral Resistance

(lb)

Specimen Number

Main MemberBearing

Length (in)Embedment

Strength (psi)Moisture Content

Specific Gravity



Bearing Length (in)





Side Members (steel)Resistance Specimen

Number

Main Member TR-12 Calculated Value

Appendix C140

5% O

ffse

t Yie

ldC

apac

ity



Mode

Set: M-0-4Bolt

M-0-4-1 13.6% 0.56 1.515 3193 0.500 139200 72160 2419 Im 2825 0.86M-0-4-2 13.6% 0.53 1.508 3169 0.500 139200 72160 2389 Im 2351 1.02M-0-4-3 12.9% 0.55 1.513 3095 0.500 139200 72160 2341 Im Error1 Error1


M-0-4-1 13.6% 0.56 1.515 8388 0.500 139200 85570 6354 Im 8125 IIIs 0.78M-0-4-2 13.6% 0.53 1.508 4598 0.500 139200 85570 3467 Im 10980 IIIs 0.32M-0-4-3 12.9% 0.55 1.513 4619 0.500 139200 85570 3494 Im Error1 IIIs Error1


1 Data acquisition error. Specimen omitted

Set: M-0-7Bolt

M-0-7-1 11.7% 0.52 1.505 3354 0.500 139200 72160 2524 Im 2605 0.97M-0-7-2 11.7% 0.53 1.503 2703 0.500 139200 72160 2031 Im 1949 1.04M-0-7-3 12.5% 0.55 1.511 2595 0.500 139200 72160 1961 Im 2053 0.96Average 11.9% 0.53 1.506 2884 0.500 139200 72160 2172 2202 0.99St. Dev 0.5% 0.02 0.004 410 0.000 0 0 307 353 0.05COV 3.8% 3.0% 0.3% 14.2% 0.0% 0.0% 0.0% 14.1% 16.0% 4.7%

M-0-7-1 11.7% 0.52 1.505 5183 0.500 139200 85570 3900 Im 6209 IIIs 0.63M-0-7-2 11.7% 0.53 1.503 5852 0.500 139200 85570 4398 Im 6766 IIIs 0.65M-0-7-3 12.5% 0.55 1.511 6148 0.500 139200 85570 4645 Im 6101 IIIs 0.76Average 11.9% 0.53 1.506 5728 0.500 139200 85570 4314 6359 0.68St. Dev 0.5% 0.02 0.004 495 0.000 0 0 379 357 0.07COV 3.8% 3.0% 0.3% 8.6% 0.0% 0.0% 0.0% 8.8% 5.6% 10.5%

Cap

acity


Yield Mode Test Resistance (lb)Resistance Specimen

Number

Main MemberEmbedment

Strength (psi)Bending Strength

(psi)

5% O

ffse

t Yie

ld

Yield Mode

Moisture Content

Specific Gravity

Bearing Length (in)


Specimen Number

Main Member Side Members (steel) TR-12 Calculated ValueYield Mode

Bearing Length (in)


Moisture Content

Specific Gravity

Calc / Test

Side Members (steel)





TR-12 Calculated Value Connection Test ResultCalc / TestBearing Length per

Side (in)

Appendix C141

Cap

acity


Resistance

5% O

ffse

t Yie

ld

Connection Test Result

Set: L-10-4Bolt

L-10-4-1 9.8% 0.61 1.646 3421 0.500 139200 72160 2815 Im 2631 1.07L-10-4-2 9.3% 0.63 1.573 3831 0.500 139200 72160 3013 Im 3182 0.95L-10-4-3 9.4% 0.72 1.557 4733 0.500 139200 72160 3685 Im 2693 1.37L-10-4-4 10.7% 0.61 1.614 3642 0.500 139200 72160 2939 Im 2482 1.18L-10-4-5 9.2% 0.66 1.500 3947 0.500 139200 72160 2690 Im 2830 0.95L-10-4-6 9.2% 0.66 1.522 4116 0.500 139200 72160 3132 Im 2354 1.33L-10-4-7 9.2% 0.64 1.521 5127 0.500 139200 72160 3899 Im 2623 1.49L-10-4-8 9.5% 0.65 1.570 4564 0.500 139200 72160 3583 Im 2567 1.40L-10-4-9 9.0% 0.67 1.563 4552 0.500 139200 72160 3557 Im 2973 1.20

L-10-4-10 8.7% 0.68 1.577 4998 0.500 139200 72160 3941 Im 3264 1.21Average 9.4% 0.65 1.564 4293 0.500 139200 72160 3325 2760 1.21St. Dev 0.5% 0.03 0.044 585 0.000 0 0 460 298 0.18COV 5.8% 5.0% 2.8% 13.6% 0.0% 0.0% 0.0% 13.8% 10.8% 15.2%

L-10-4-1 9.8% 0.61 1.646 4683 0.500 139200 85570 4683 Im 2703 S 1.73L-10-4-2 9.3% 0.63 1.573 5686 0.500 139200 85570 4472 Im 3373 S 1.33L-10-4-3 9.4% 0.72 1.557 7062 0.500 139200 85570 5498 Im 3017 S 1.82L-10-4-4 10.7% 0.61 1.614 5976 0.500 139200 85570 4823 Im 2522 S 1.91L-10-4-5 9.2% 0.66 1.500 5532 0.500 139200 85570 4149 Im 2956 S 1.40L-10-4-6 9.2% 0.66 1.522 5893 0.500 139200 85570 4485 Im 2458 S 1.82L-10-4-7 9.2% 0.64 1.521 6743 0.500 139200 85570 5128 Im 2731 S 1.88L-10-4-8 9.5% 0.65 1.570 6103 0.500 139200 85570 4791 Im 3177 S 1.51L-10-4-9 9.0% 0.67 1.563 6271 0.500 139200 85570 4901 Im 3142 S 1.56

L-10-4-10 8.7% 0.68 1.577 6943 0.500 139200 85570 5475 Im 3272 S 1.67Average 9.4% 0.65 1.564 6089 0.500 139200 85570 4841 2935 1.66St. Dev 0.5% 0.03 0.044 718 0.000 0 0 433 318 0.21COV 5.8% 5.0% 2.8% 11.8% 0.0% 0.0% 0.0% 8.9% 10.8% 12.4%

Moisture Content



Specimen Number


Bearing Length (in)


Calc / TestSpecific Gravity



Appendix C142

Cap

acity


Resistance

5% O

ffse

t Yie

ld


Set: L-5-4Bolt

L-5-4-1 9.3% 0.66 1.600 4463 0.500 139200 72160 3570 Im 2668 1.34L-5-4-2 9.5% 0.63 1.582 3835 0.500 139200 72160 3033 Im 2474 1.23L-5-4-3 9.6% 0.66 1.494 4468 0.500 139200 72160 3338 Im 2639 1.26L-5-4-4 9.5% 0.66 1.526 4699 0.500 139200 72160 3585 Im 2484 1.44L-5-4-5 9.5% 0.62 1.574 4051 0.500 139200 72160 3188 Im 2419 1.32L-5-4-6 9.6% 0.63 1.571 4166 0.500 139200 72160 3272 Im 2394 1.37Average 9.5% 0.64 1.558 4280 0.500 139200 72160 3331 2513 1.33St. Dev 0.1% 0.02 0.040 319 0.000 0 0 217 114 0.08COV 1.1% 3.0% 2.5% 7.4% 0.0% 0.0% 0.0% 6.5% 4.5% 5.8%

L-5-4-1 9.3% 0.66 1.600 7407 0.500 139200 85570 5926 Im 2693 S 2.20L-5-4-2 9.5% 0.63 1.582 5054 0.500 139200 85570 3998 Im 2567 S 1.56L-5-4-3 9.6% 0.66 1.494 5658 0.500 139200 85570 4227 Im 3153 S 1.34L-5-4-4 9.5% 0.66 1.526 6199 0.500 139200 85570 4730 Im 2636 S 1.79L-5-4-5 9.5% 0.62 1.574 5873 0.500 139200 85570 4622 Im 2864 S 1.61L-5-4-6 9.6% 0.63 1.571 4968 0.500 139200 85570 3902 Im 2912 S 1.34Average 9.5% 0.64 1.558 5860 0.500 139200 85570 4568 2804 1.64St. Dev 0.1% 0.02 0.040 894 0.000 0 0 743 216 0.32COV 1.1% 3.0% 2.5% 15.3% 0.0% 0.0% 0.0% 16.3% 7.7% 19.7%

Set: L-5-7Bolt


L-5-7-1 9.4% 0.62 1.594 6681 0.500 139200 85570 5325 Im 4068 S 1.31L-5-7-2 9.3% 0.62 1.587 6450 0.500 139200 85570 5118 Im 5174 S 0.99L-5-7-3 9.5% 0.60 1.538 6807 0.500 139200 85570 5235 Im 4433 Im-S 1.18L-5-7-4 9.4% 0.64 1.569 5066 0.500 139200 85570 3974 Im 4060 Im-S 0.98L-5-7-5 9.2% 0.63 1.532 5040 0.500 139200 85570 3861 Im 3957 S 0.98L-5-7-6 9.5% 0.61 1.588 5449 0.500 139200 85570 4327 Im 5081 Im-S 0.85Average 9.4% 0.62 1.568 5916 0.500 139200 85570 4640 4462 1.05St. Dev 0.1% 0.02 0.027 821 0.000 0 0 663 541 0.17COV 1.3% 2.4% 1.7% 13.9% 0.0% 0.0% 0.0% 14.3% 12.1% 15.8%





Cap

acity


Resistance

5% O

ffse

t Yie

ld


(lb)

Specimen Number

Main MemberBearing



Specific Gravity



Bearing Length (in)






Number


Appendix C143

5% O

ffse

t Yie

ldC

apac

ity



Mode

Set: L-5-10Bolt


L-5-10-1 9.5% 0.65 1.576 6205 0.500 139200 85570 4890 Im 6972 IIIs-S 0.70L-5-10-2 9.8% 0.64 1.597 7608 0.500 139200 85570 6075 Im 7034 IIIs-S 0.86L-5-10-3 9.6% 0.63 1.573 6332 0.500 139200 85570 4980 Im 7069 IIIs-S 0.70L-5-10-4 9.8% 0.61 1.604 5462 0.500 139200 85570 4381 Im 5961 IIIs-S 0.73L-5-10-5 9.2% 0.65 1.533 5807 0.500 139200 85570 4451 Im 6449 IIIs-S 0.69L-5-10-6 9.8% 0.63 1.572 5983 0.500 139200 85570 4703 Im 6546 IIIs-S 0.72Average 9.6% 0.64 1.576 6233 0.500 139200 85570 4913 6672 0.74St. Dev 0.2% 0.02 0.025 740 0.000 0 0 616 436 0.06COV 2.5% 2.4% 1.6% 11.9% 0.0% 0.0% 0.0% 12.5% 6.5% 8.8%

Set: L-3-4Bolt


L-3-4-1 9.7% 0.66 1.505 5086 0.500 139200 85570 3827 Im 2820 S 1.36L-3-4-2 9.7% 0.66 1.591 5096 0.500 139200 85570 4054 Im 2866 S 1.41L-3-4-3 9.8% 0.69 1.513 6637 0.500 139200 85570 5021 Im 2574 S 1.95L-3-4-4 10.3% 0.65 1.607 6080 0.500 139200 85570 4885 Im 2858 S 1.71L-3-4-5 9.5% 0.65 1.590 5872 0.500 139200 85570 4668 Im 2578 S 1.81L-3-4-6 9.7% 0.62 1.606 5518 0.500 139200 85570 4431 Im 2501 S 1.77Average 9.8% 0.65 1.569 5715 0.500 139200 85570 4481 2700 1.67St. Dev 0.3% 0.02 0.047 604 0.000 0 0 470 166 0.23COV 2.8% 3.5% 3.0% 10.6% 0.0% 0.0% 0.0% 10.5% 6.1% 14.0%

Cap

acity



Number



(psi)

5% O

ffse

t Yie

ld

Yield Mode

Moisture Content

Specific Gravity

Bearing Length (in)


Specimen Number


Bearing Length (in)


Moisture Content

Specific Gravity

Calc / Test







Side (in)

Appendix C144

Cap

acity


Resistance

5% O

ffse

t Yie

ld


Set: L-0-4Bolt

L-0-4-1 10.0% 0.64 1.603 4559 0.500 139200 72160 3654 Im 3506 1.04L-0-4-2 10.0% 0.66 1.506 4040 0.500 139200 72160 3042 Im 3301 0.92L-0-4-3 9.9% 0.63 1.569 4689 0.500 139200 72160 3679 Im 3692 1.00Average 10.0% 0.64 1.559 4429 0.500 139200 72160 3458 3500 0.99St. Dev 0.1% 0.02 0.049 344 0.000 0 0 361 196 0.06COV 0.8% 2.3% 3.1% 7.8% 0.0% 0.0% 0.0% 10.4% 5.6% 6.2%

L-0-4-1 10.0% 0.64 1.603 5071 0.500 139200 85570 4064 Im 9636 IIIs 0.42L-0-4-2 10.0% 0.66 1.506 5898 0.500 139200 85570 4441 Im 7415 IIIs 0.60L-0-4-3 9.9% 0.63 1.569 6572 0.500 139200 85570 5156 Im 9745 IIIs 0.53Average 10.0% 0.64 1.559 5847 0.500 139200 85570 4554 8932 0.52St. Dev 0.1% 0.02 0.049 752 0.000 0 0 555 1315 0.09COV 0.8% 2.3% 3.1% 12.9% 0.0% 0.0% 0.0% 12.2% 14.7% 17.3%

Set: L-0-7Bolt

L-0-7-1 10.2% 0.68 1.619 4728 0.500 139200 72160 3827 Im 3782 1.01L-0-7-2 10.3% 0.66 1.617 3902 0.500 139200 72160 3155 Im 4009 0.79L-0-7-3 10.3% 0.57 1.626 4263 0.500 139200 72160 3466 Im 3499 0.99Average 10.3% 0.64 1.621 4298 0.500 139200 72160 3483 3763 0.93St. Dev 0.0% 0.06 0.005 414 0.000 0 0 336 256 0.12COV 0.3% 9.4% 0.3% 9.6% 0.0% 0.0% 0.0% 9.7% 6.8% 13.4%

L-0-7-1 10.2% 0.68 1.619 6209 0.500 139200 85570 5026 Im 8318 IIIs 0.60L-0-7-2 10.3% 0.66 1.617 4916 0.500 139200 85570 3975 Im 9279 IIIs 0.43L-0-7-3 10.3% 0.57 1.626 5832 0.500 139200 85570 4741 Im 8676 IIIs 0.55Average 10.3% 0.64 1.621 5652 0.500 139200 85570 4581 8758 0.53St. Dev 0.0% 0.06 0.005 665 0.000 0 0 544 486 0.09COV 0.3% 9.4% 0.3% 11.8% 0.0% 0.0% 0.0% 11.9% 5.5% 17.0%

Specimen Number Embedment

Strength (psi)

Cap

acity


Resistance

5% O

ffse

t Yie

ld

Connection Test ResultCalc / TestLateral Resistance

(lb)


Bearing Length (in)


Moisture Content

Specific Gravity




Calc / TestMoisture Content

Specific Gravity

Bearing Length (in)





Resistance Specimen Number

Main Member TR-12 Calculated ValueSide Members (steel)

Appendix C145

5% O

ffse

t Yie

ldC

apac

ity



Mode

Set: P-10-4Bolt

P-10-4-3 8.6% 0.64 1.512 3231 0.500 139200 72160 2443 Im 2713 0.90P-10-4-4 8.8% 0.61 1.519 2426 0.500 139200 72160 1843 Im 1958 0.94P-10-4-5 8.9% 0.63 1.517 2710 0.500 139200 72160 2056 Im 2061 1.00P-10-4-6 9.2% 0.64 1.495 3147 0.500 139200 72160 2352 Im 2758 0.85P-10-4-7 9.3% 0.61 1.526 2981 0.500 139200 72160 2275 Im 2155 1.06P-10-4-8 8.8% 0.62 1.508 2837 0.500 139200 72160 2139 Im 2634 0.81P-10-4-9 10.8% 0.64 1.486 2771 0.500 139200 72160 2059 Im 2364 0.87

P-10-4-10 9.1% 0.61 1.509 3176 0.500 139200 72160 2396 Im 3101 0.77P-10-4-11 9.0% 0.66 1.478 4589 0.500 139200 72160 3391 Im 1984 1.71P-10-4-12 8.9% 0.67 1.519 3560 0.500 139200 72160 2704 Im 2327 1.16Average 9.1% 0.63 1.507 3143 0.500 139200 72160 2366 2406 1.01St. Dev 0.6% 0.02 0.016 599 0.000 0 0 434 383 0.27COV 6.7% 3.3% 1.0% 19.1% 0.0% 0.0% 0.0% 18.3% 15.9% 27.1%

P-10-4-3 8.6% 0.64 1.512 6569 0.500 139200 85570 4966 Im 3368 S 1.47P-10-4-4 8.8% 0.61 1.519 4947 0.500 139200 85570 3757 Im 3231 S 1.16P-10-4-5 8.9% 0.63 1.517 7916 0.500 139200 85570 6004 Im 3138 S 1.91P-10-4-6 9.2% 0.64 1.495 5728 0.500 139200 85570 4282 Im 3665 S 1.17P-10-4-7 9.3% 0.61 1.526 6589 0.500 139200 85570 5027 Im 2759 S 1.82P-10-4-8 8.8% 0.62 1.508 4222 0.500 139200 85570 3183 Im 3985 S 0.80P-10-4-9 10.8% 0.64 1.486 4862 0.500 139200 85570 3612 Im 3317 S 1.09

P-10-4-10 9.1% 0.61 1.509 5743 0.500 139200 85570 4333 Im 3961 S 1.09P-10-4-11 9.0% 0.66 1.478 7878 0.500 139200 85570 5822 Im 3015 S 1.93P-10-4-12 8.9% 0.67 1.519 6616 0.500 139200 85570 5025 Im 3337 S 1.51Average 9.1% 0.63 1.507 6107 0.500 139200 85570 4601 3378 1.40St. Dev 0.6% 0.02 0.016 1240 0.000 0 0 933 393 0.39COV 6.7% 3.3% 1.0% 20.3% 0.0% 0.0% 0.0% 20.3% 11.6% 28.3%

Calc / TestSpecimen Number

Main MemberYield Mode

Moisture Content


Cap

acity

Test Resistance (lb)Resistance

5% O

ffse

t Yie

ld

Connection Test ResultTR-12 Calculated ValueYield Mode

Appendix C146

Specific Gravity



Bearing Length (in)




Set: P-5-4Bolt

P-5-4-1 8.3% 0.62 1.528 2996 0.500 139200 72160 2289 Im 1828 1.25P-5-4-2 8.8% 0.62 1.521 3227 0.500 139200 72160 2454 Im 1985 1.24P-5-4-3 8.3% 0.64 1.520 3210 0.500 139200 72160 2440 Im 2065 1.18P-5-4-4 8.6% 0.58 1.515 3289 0.500 139200 72160 2491 Im 2025 1.23P-5-4-5 8.4% 0.68 1.525 2904 0.500 139200 72160 2214 Im 2822 0.78P-5-4-6 9.2% 0.64 1.530 3747 0.500 139200 72160 2866 Im 1846 1.55Average 8.6% 0.63 1.523 3229 0.500 139200 72160 2459 2095 1.21St. Dev 0.4% 0.03 0.005 294 0.000 0 0 226 369 0.25COV 4.1% 5.4% 0.4% 9.1% 0.0% 0.0% 0.0% 9.2% 17.6% 20.4%

P-5-4-1 8.3% 0.62 1.528 6317 0.500 139200 85570 4826 Im 3106 S 1.55P-5-4-2 8.8% 0.62 1.521 5152 0.500 139200 85570 3918 Im 2945 S 1.33P-5-4-3 8.3% 0.64 1.520 6925 0.500 139200 85570 5263 Im 2437 S 2.16P-5-4-4 8.6% 0.58 1.515 5940 0.500 139200 85570 4500 Im 2747 S 1.64P-5-4-5 8.4% 0.68 1.525 4183 0.500 139200 85570 3190 Im 3527 Im 0.90P-5-4-6 9.2% 0.64 1.530 5047 0.500 139200 85570 3861 Im 3285 S 1.18Average 8.6% 0.63 1.523 5594 0.500 139200 85570 4260 3008 1.46St. Dev 0.4% 0.03 0.005 990 0.000 0 0 749 388 0.43COV 4.1% 5.4% 0.4% 17.7% 0.0% 0.0% 0.0% 17.6% 12.9% 29.6%

Set: P-5-7Bolt


P-5-7-1 9.0% 0.60 1.511 4891 0.500 139200 85570 3695 Im 4303 Im-S 0.86P-5-7-2 9.4% 0.63 1.491 6041 0.500 139200 85570 4504 Im 5281 Im-S 0.85P-5-7-3 8.4% 0.60 1.522 4428 0.500 139200 85570 3370 Im 4773 Im-S 0.71P-5-7-4 8.1% 0.59 1.516 7109 0.500 139200 85570 5389 Im 4368 Im-S 1.23P-5-7-5 9.3% 0.62 1.513 6737 0.500 139200 85570 5097 Im 5079 Im-S 1.00P-5-7-6 8.4% 0.60 1.533 4985 0.500 139200 85570 3821 Im 5128 Im-S 0.75Average 8.8% 0.61 1.514 5699 0.500 139200 85570 4313 4822 0.90St. Dev 0.6% 0.01 0.014 1092 0.000 0 0 815 412 0.19COV 6.4% 2.2% 0.9% 19.2% 0.0% 0.0% 0.0% 18.9% 8.5% 21.5%





Cap

acity


Resistance

5% O

ffse

t Yie

ld


(lb)

Specimen Number

Main MemberBearing



Specific Gravity



Bearing Length (in)






Number


Appendix C147

5% O

ffse

t Yie

ldC

apac

ity



Mode

Set: P-5-10Bolt


P-5-10-1 8.5% 0.69 1.518 6561 0.500 139200 85570 4980 Im 7188 Im-S 0.69P-5-10-2 8.6% 0.65 1.524 6692 0.500 139200 85570 5099 Im 7412 IIIs-S 0.69P-5-10-3 8.9% 0.61 1.479 4024 0.500 139200 85570 2976 Im 6930 Im-S 0.43P-5-10-4 9.0% 0.66 1.503 5653 0.500 139200 85570 4248 Im 6399 Im-S 0.66P-5-10-5 8.6% 0.68 1.519 6910 0.500 139200 85570 5248 Im 7923 IIIs-S 0.66P-5-10-6 8.8% 0.61 1.512 6653 0.500 139200 85570 5030 Im 7023 IIIs-S 0.72Average 8.7% 0.65 1.509 6082 0.500 139200 85570 4597 7146 0.64St. Dev 0.2% 0.03 0.017 1098 0.000 0 0 867 509 0.11COV 2.3% 5.3% 1.1% 18.1% 0.0% 0.0% 0.0% 18.9% 7.1% 16.5%

Set: P-3-4Bolt


P-3-4-1 9.2% 0.57 1.514 5055 0.500 139200 85570 3827 Im 3379 Im-S 1.13P-3-4-2 8.7% 0.61 1.515 5945 0.500 139200 85570 4503 Im 3171 Im-S 1.42P-3-4-3 8.7% 0.62 1.523 5283 0.500 139200 85570 4023 Im 2566 Im-S 1.57P-3-4-4 8.8% 0.61 1.521 7324 0.500 139200 85570 5570 Im 3241 S 1.72P-3-4-5 9.0% 0.63 1.516 7511 0.500 139200 85570 5693 Im 3600 S 1.58P-3-4-6 8.9% 0.64 1.516 6603 0.500 139200 85570 5005 Im 2910 Im-S 1.72Average 8.9% 0.61 1.517 6287 0.500 139200 85570 4770 3145 1.52St. Dev 0.2% 0.02 0.004 1031 0.000 0 0 783 364 0.22COV 2.2% 3.8% 0.2% 16.4% 0.0% 0.0% 0.0% 16.4% 11.6% 14.5%

Cap

acity



Number



(psi)

5% O

ffse

t Yie

ld

Yield Mode

Moisture Content

Specific Gravity

Bearing Length (in)


Specimen Number


Bearing Length (in)


Moisture Content

Specific Gravity

Calc / Test







Side (in)

Appendix C148

Cap

acity


Resistance

5% O

ffse

t Yie

ld


Set: P-0-4Bolt


P-0-4-1 8.7% 0.67 1.520 6929 0.500 139200 85570 5266 Im 10176 IIIs 0.52P-0-4-2 8.8% 0.62 1.506 7647 0.500 139200 85570 5758 Im 8898 IIIs 0.65P-0-4-3 9.4% 0.60 1.505 5063 0.500 139200 85570 3810 Im 8026 IIIs 0.47Average 9.0% 0.63 1.510 6546 0.500 139200 85570 4945 9033 0.55St. Dev 0.4% 0.04 0.008 1334 0.000 0 0 1013 1081 0.09COV 4.5% 5.8% 0.5% 20.4% 0.0% 0.0% 0.0% 20.5% 12.0% 16.4%

Set: P-0-7Bolt


P-0-7-1 9.5% 0.64 1.520 6558 0.500 139200 85570 4984 Im 9221 IIIs 0.54P-0-7-2 9.0% 0.66 1.522 6885 0.500 139200 85570 5239 Im 8224 IIIs 0.64P-0-7-3 9.0% 0.61 1.520 6401 0.500 139200 85570 4865 Im 9824 IIIs 0.50Average 9.2% 0.64 1.521 6615 0.500 139200 85570 5029 9090 0.56St. Dev 0.3% 0.02 0.001 247 0.000 0 0 191 808 0.07COV 3.6% 3.8% 0.1% 3.7% 0.0% 0.0% 0.0% 3.8% 8.9% 13.0%

5% O

ffse

t Yie

ldC

apac

ity



ModeResistance Specimen

Number

Main Member TR-12 Calculated Value Connection Test ResultCalc / TestMoisture


Bearing Length (in)





Yield Mode

Bearing Length (in)


Moisture Content

Specific Gravity

Calc / TestLateral Resistance (lb)

Specimen Number





Main Member Side Members (steel) TR-12 Calculated ValueAppendix C

149C

apac

ity


Resistance

5% O

ffse

t Yie

ld


Appendix D - Fracture Calculations (with Inputs)All model calculations performed in SI units, with results then converted back to Imperial units.Conversions: 1 in. = 25.4 mm; 1 lb = 4.4482 N; 1psi = 0.0068948 N/mm2; 1 lb/in = 0.1751 N/mm

Set: M-10-4Test Result

M-10-4-1 10.8% 0.58 1.515 1.66E+05 4.73 1.90E+06 363 3211 5744 1.79 6335 1.97M-10-4-2 11.0% 0.51 1.512 1.66E+05 4.60 1.90E+06 329 2434 5655 2.32 6270 2.58M-10-4-3 10.4% 0.43 1.510 1.66E+05 3.37 1.90E+06 242 1972 4837 2.45 5410 2.74M-10-4-4 11.6% 0.67 1.513 1.66E+05 6.95 1.90E+06 468 4184 6963 1.66 7639 1.83M-10-4-5 11.7% 0.58 1.518 1.66E+05 5.30 1.90E+06 391 3541 6095 1.72 6711 1.90M-10-4-6 9.9% 0.65 1.521 1.66E+05 6.34 1.90E+06 477 4143 6680 1.61 7303 1.76M-10-4-7 11.2% 0.45 1.502 1.66E+05 2.14 1.90E+06 190 2113 3832 1.81 4287 2.03M-10-4-8 10.1% 0.69 1.513 1.66E+05 9.62 1.90E+06 402 4668 8188 1.75 9167 1.96M-10-4-9 12.4% 0.57 1.516 1.66E+05 4.11 1.90E+06 424 3169 5367 1.69 5819 1.84M-10-4-10 10.5% 0.59 1.515 1.66E+05 3.86 1.90E+06 396 3334 5191 1.56 5650 1.69

Average 11.0% 0.57 1.513 1.66E+05 5.10 1.90E+06 368 3277 5855 1.84 6459 2.03St. Dev 0.8% 0.09 0.005 0.00E+00 2.11 2.45E-10 92 905 1214 0.30 1351 0.35COV 7.2% 15.3% 0.3% 0.0% 41.4% 0.0% 25.0% 27.6% 20.7% 16.4% 20.9% 17.2%


M-5-4-1 13.2% 0.47 1.495 1.66E+05 1.51 1.90E+06 227 1725 3215 1.86 3515 2.04M-5-4-2 13.5% 0.53 1.511 1.66E+05 1.85 1.90E+06 361 2419 3592 1.48 3824 1.58M-5-4-3 11.8% 0.67 1.506 1.66E+05 7.26 1.90E+06 341 3469 7072 2.04 7934 2.29M-5-4-4 14.1% 0.54 1.503 1.66E+05 2.02 1.90E+06 244 2124 3725 1.75 4098 1.93M-5-4-5 11.8% 0.56 1.536 1.66E+05 5.53 1.90E+06 479 3470 6305 1.82 6856 1.98M-5-4-6 11.4% 0.42 1.522 1.66E+05 2.45 1.90E+06 166 2537 4155 1.64 4706 1.85Average 12.6% 0.53 1.512 1.66E+05 3.44 1.90E+06 303 2624 4677 1.77 5156 1.94St. Dev 1.1% 0.08 0.015 0.00E+00 2.37 0.00E+00 113 712 1605 0.19 1811 0.23COV 8.5% 15.6% 1.0% 0.0% 69.1% 0.0% 37.2% 27.1% 34.3% 10.8% 35.1% 11.9%

Capacity Resistance

(lb)Calc / Test

Jensen Model

Moisture Content

Specific Gravity Width (in)

Shear Modulus

(psi)

Fracture Energy (lb/in)

Modulus of Elasticity (psi)

Tension Perp Strength (psi)

Jensen ModelCapacity

Resistance (lb)

Calc / TestCapacity Resistance (lb) Calc / Test

Main Member Van der Put Model

Calc / Test

Moisture Content

Specific Gravity

Shear Modulus

(psi)


Capacity Resistance (lb)



150Appendix D

Note: Van der Put / Leijten model calculations have been converted into maximum connection resistance, P (where P = 2*V for a connection at midspan)


Specimen Number


Width (in) Tension Perp Strength (psi)

Specimen Number







Capacity Resistance

(lb)Calc / TestTension Perp

Strength (psi)Capacity

Resistance (lb)Capacity

Resistance (lb) Calc / TestSpecimen Number

Main Member Van der Put Model Jensen Model

Moisture Content

Specific Gravity Width (in) Shear Modulus

(psi)Fracture

Energy (lb/in)

Modulus of Elasticity

(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)

Specimen Number


Calc / TestCapacity Resistance (lb)




Capacity Resistance (lb) Calc / Test

Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Appendix D151

Jensen Model

Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)



M-0-4-1 13.6% 0.56 1.515 1.66E+05 3.39 1.90E+06 425 8125 4875 0.60 5248 0.65M-0-4-2 13.6% 0.53 1.508 1.66E+05 3.00 1.90E+06 389 10980 4562 0.42 4917 0.45M-0-4-3 12.9% 0.55 1.513 1.66E+05 4.17 1.90E+06 354 Error1 5399 Error1 5930 Error1

Average 13.4% 0.55 1.512 1.66E+05 3.52 1.90E+06 389 9553 4945 0.51 5365 0.55St. Dev 0.4% 0.01 0.004 0.00E+00 0.60 0.00E+00 36 2019 423 0.13 516 0.14COV 3.3% 2.4% 0.3% 0.0% 17.0% 0.0% 9.1% 21.1% 8.6% 25.7% 9.6% 25.6%

1 Error during data acquisition. Specimen Omitted


M-0-7-1 11.7% 0.52 1.505 1.66E+05 3.25 1.90E+06 256 6209 7410 1.19 6854 1.10M-0-7-2 11.7% 0.53 1.503 1.66E+05 3.16 1.90E+06 436 6766 7298 1.08 6471 0.96M-0-7-3 12.5% 0.55 1.511 1.66E+05 2.77 1.90E+06 420 6101 6871 1.13 6076 1.00Average 11.9% 0.53 1.506 1.66E+05 3.06 1.90E+06 370 6359 7193 1.13 6467 1.02St. Dev 0.5% 0.02 0.004 0.00E+00 0.26 0.00E+00 100 357 285 0.06 389 0.08COV 3.8% 3.0% 0.3% 0.0% 8.4% 0.0% 26.9% 5.6% 4.0% 5.1% 6.0% 7.5%

Set: L-10-4Test Result

L-10-4-1 9.8% 0.61 1.646 1.04E+05 12.81 2.33E+06 127 2703 8161 3.02 9434 3.49L-10-4-2 9.3% 0.63 1.573 1.04E+05 6.93 2.33E+06 135 3373 5738 1.70 6534 1.94L-10-4-3 9.4% 0.72 1.557 1.04E+05 6.98 2.33E+06 81 3017 5700 1.89 6617 2.19L-10-4-4 10.7% 0.61 1.614 1.04E+05 11.81 2.33E+06 135 2522 7694 3.05 8850 3.51L-10-4-5 9.2% 0.66 1.500 1.04E+05 7.77 2.33E+06 143 2956 5791 1.96 6598 2.23L-10-4-6 9.2% 0.66 1.522 1.04E+05 11.56 2.33E+06 107 2458 7169 2.92 8323 3.39L-10-4-7 9.2% 0.64 1.521 1.04E+05 8.52 2.33E+06 81 2731 6147 2.25 7165 2.62L-10-4-8 9.5% 0.65 1.570 1.04E+05 7.50 2.33E+06 89 3177 5958 1.88 6908 2.17L-10-4-9 9.0% 0.67 1.563 1.04E+05 7.98 2.33E+06 125 3142 6114 1.95 7011 2.23

L-10-4-10 8.7% 0.68 1.577 1.04E+05 5.52 2.33E+06 109 3272 5132 1.57 5873 1.79Average 9.4% 0.65 1.564 1.04E+05 8.74 2.33E+06 113 2935 6360 2.22 7331 2.56St. Dev 0.5% 0.03 0.044 0.00E+00 2.45 0.00E+00 23 318 977 0.57 1147 0.66COV 5.8% 5.0% 2.8% 0.0% 28.0% 0.0% 20.7% 10.8% 15.4% 25.5% 15.6% 25.8%

Calc / Test

Calc / Test

Jensen Model

Moisture Content


Shear Modulus

(psi)




Capacity Resistance

(lb)


Capacity Resistance

(lb)

Van der Put Model




Moisture Content

Specimen Number


Capacity Resistance

(lb)

Jensen Model

Moisture Content


Shear Modulus

(psi)


Specimen Number

Main Member




Specimen Number


Shear Modulus

(psi)

Appendix D152




Calc / TestCapacity Resistance (lb) Calc / Test



L-5-4-1 9.3% 0.66 1.600 1.04E+05 8.15 2.33E+06 158 2693 6321 2.35 7183 2.67L-5-4-2 9.5% 0.63 1.582 1.04E+05 6.67 2.33E+06 104 2567 5655 2.20 6510 2.54L-5-4-3 9.6% 0.66 1.494 1.04E+05 12.05 2.33E+06 142 3153 7178 2.28 8262 2.62L-5-4-4 9.5% 0.66 1.526 1.04E+05 8.01 2.33E+06 124 2636 5976 2.27 6862 2.60L-5-4-5 9.5% 0.62 1.574 1.04E+05 6.20 2.33E+06 103 2864 5425 1.89 6242 2.18L-5-4-6 9.6% 0.63 1.571 1.04E+05 8.83 2.33E+06 81 2912 6465 2.22 7539 2.59Average 9.5% 0.64 1.558 1.04E+05 8.32 2.33E+06 119 2804 6170 2.20 7100 2.53St. Dev 0.1% 0.02 0.040 0.00E+00 2.07 0.00E+00 28 216 630 0.16 734 0.18COV 1.1% 3.0% 2.5% 0.0% 24.9% 0.0% 23.9% 7.7% 10.2% 7.2% 10.3% 7.0%







(psi)





Specimen Number




Moisture Content


(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)




Appendix D153

Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Jensen Model




L-0-4-1 10.0% 0.64 1.603 1.04E+05 7.20 2.33E+06 117 9636 5952 0.62 6834 0.71L-0-4-2 10.0% 0.66 1.506 1.04E+05 4.62 2.33E+06 108 7415 4483 0.60 5114 0.69L-0-4-3 9.9% 0.63 1.569 1.04E+05 5.76 2.33E+06 133 9745 5211 0.53 5919 0.61Average 10.0% 0.64 1.559 1.04E+05 5.86 2.33E+06 120 8932 5215 0.59 5955 0.67St. Dev 0.1% 0.02 0.049 0.00E+00 1.29 0.00E+00 13 1315 734 0.04 861 0.05COV 0.8% 2.3% 3.1% 0.0% 22.0% 0.0% 10.6% 14.7% 14.1% 7.6% 14.5% 8.1%


L-0-7-1 10.2% 0.68 1.619 1.04E+05 7.29 2.33E+06 76 8318 9479 1.14 9245 1.11L-0-7-2 10.3% 0.66 1.617 1.04E+05 8.19 2.33E+06 65 9279 10028 1.08 9859 1.06L-0-7-3 10.3% 0.57 1.626 1.04E+05 6.24 2.33E+06 102 8676 8810 1.02 8462 0.98Average 10.3% 0.64 1.621 1.04E+05 7.24 2.33E+06 81 8758 9439 1.08 9189 1.05St. Dev 0.0% 0.06 0.005 0.00E+00 0.98 0.00E+00 19 486 610 0.06 700 0.07COV 0.3% 9.4% 0.3% 0.0% 13.5% 0.0% 23.5% 5.5% 6.5% 5.8% 7.6% 6.6%

Capacity Resistance

(lb)Calc / TestTension Perp

Strength (psi)Capacity

Resistance (lb)Capacity

Resistance (lb) Calc / TestSpecimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)

Specimen Number







Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Appendix D154

Jensen Model

Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)


Set: P-10-4Test Result

P-10-4-3 8.6% 0.64 1.512 9.83E+04 11.66 2.21E+06 179 3368 6928 2.06 7893 2.34P-10-4-4 8.8% 0.61 1.519 9.83E+04 7.00 2.21E+06 172 3231 5383 1.67 6077 1.88P-10-4-5 8.9% 0.63 1.517 9.83E+04 9.79 2.21E+06 81 3138 6363 2.03 7449 2.37P-10-4-6 9.2% 0.64 1.495 9.83E+04 14.47 2.21E+06 195 3665 7627 2.08 8703 2.37P-10-4-7 9.3% 0.61 1.526 9.83E+04 9.88 2.21E+06 125 2759 6428 2.33 7421 2.69P-10-4-8 8.8% 0.62 1.508 9.83E+04 7.40 2.21E+06 117 3985 5517 1.38 6328 1.59P-10-4-9 10.8% 0.64 1.486 9.83E+04 21.14 2.21E+06 91 3317 9171 2.76 10798 3.26

P-10-4-10 9.1% 0.61 1.509 9.83E+04 11.91 2.21E+06 151 3961 6973 1.76 8023 2.03P-10-4-11 9.0% 0.66 1.478 9.83E+04 14.99 2.21E+06 139 3015 7700 2.55 8890 2.95P-10-4-12 8.9% 0.67 1.519 9.83E+04 14.72 2.21E+06 168 3337 7814 2.34 8979 2.69Average 9.1% 0.63 1.507 9.83E+04 12.30 2.21E+06 142 3378 6990 2.10 8056 2.42St. Dev 0.6% 0.02 0.016 1.53E-11 4.23 4.91E-10 38 393 1146 0.42 1382 0.50COV 6.7% 3.3% 1.0% 0.0% 34.4% 0.0% 26.8% 11.6% 16.4% 20.0% 17.2% 20.8%


P-5-4-1 8.3% 0.62 1.528 9.83E+04 13.37 2.21E+06 55 3106 7481 2.41 8874 2.86P-5-4-2 8.8% 0.62 1.521 9.83E+04 14.09 2.21E+06 223 2945 7658 2.60 8677 2.95P-5-4-3 8.3% 0.64 1.520 9.83E+04 11.60 2.21E+06 193 2437 6935 2.85 7887 3.24P-5-4-4 8.6% 0.58 1.515 9.83E+04 14.97 2.21E+06 98 2747 7850 2.86 9205 3.35P-5-4-5 8.4% 0.68 1.525 9.83E+04 8.54 2.21E+06 145 3527 5969 1.69 6834 1.94P-5-4-6 9.2% 0.64 1.530 9.83E+04 21.77 2.21E+06 169 3285 9577 2.92 11085 3.37Average 8.6% 0.63 1.523 9.83E+04 14.06 2.21E+06 147 3008 7578 2.55 8760 2.95St. Dev 0.4% 0.03 0.005 1.59E-11 4.41 0.00E+00 62 388 1191 0.46 1421 0.54COV 4.1% 5.4% 0.4% 0.0% 31.4% 0.0% 42.2% 12.9% 15.7% 18.1% 16.2% 18.3%

Specimen Number


Width (in) Tension Perp Strength (psi)

Moisture Content

Specific Gravity

Shear Modulus

(psi)



Specimen Number







Jensen ModelCapacity

Resistance (lb)

Calc / TestCapacity Resistance (lb) Calc / TestCapacity

Resistance (lb)

Moisture Content


Shear Modulus

(psi)

Appendix D155

Capacity Resistance

(lb)Calc / Test

Jensen Model









(psi)





Specimen Number




Moisture Content


(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)

Specimen Number


Moisture Content


(psi)Fracture

Energy (lb/in)


(psi)




Appendix D156

Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Capacity Resistance

(lb)Calc / Test

Jensen Model


P-0-4-1 8.7% 0.67 1.520 9.83E+04 23.77 2.21E+06 169 10176 9966 0.98 11519 1.13P-0-4-2 8.8% 0.62 1.506 9.83E+04 19.00 2.21E+06 182 8898 8820 0.99 10137 1.14P-0-4-3 9.4% 0.60 1.505 9.83E+04 10.36 2.21E+06 151 8026 6502 0.81 7442 0.93Average 9.0% 0.63 1.510 9.83E+04 17.71 2.21E+06 168 9033 8429 0.93 9699 1.07St. Dev 0.4% 0.04 0.008 1.78E-11 6.79 0.00E+00 16 1081 1765 0.10 2073 0.12COV 4.5% 5.8% 0.5% 0.0% 38.4% 0.0% 9.4% 12.0% 20.9% 10.9% 21.4% 11.3%


P-0-7-1 9.5% 0.64 1.520 9.83E+04 17.62 2.21E+06 252 9221 13425 1.46 12617 1.37P-0-7-2 9.0% 0.66 1.522 9.83E+04 13.31 2.21E+06 120 8224 11669 1.42 11320 1.38P-0-7-3 9.0% 0.61 1.520 9.83E+04 25.87 2.21E+06 114 9824 16311 1.66 15989 1.63Average 9.2% 0.64 1.521 9.83E+04 18.93 2.21E+06 162 9090 13802 1.51 13309 1.46St. Dev 0.3% 0.02 0.001 1.78E-11 6.38 0.00E+00 78 808 2344 0.13 2410 0.15COV 3.6% 3.8% 0.1% 0.0% 33.7% 0.0% 48.2% 8.9% 17.0% 8.6% 18.1% 10.1%


Capacity Resistance

(lb)Calc / Test

Specimen Number








Capacity Resistance

(lb)Calc / Test

Specimen Number


Moisture Content


Shear Modulus

(psi)

Appendix D157

Jensen Model

Moisture Content


Shear Modulus

(psi)




Appendix E 158

Appendix E - Material Property Test DataNote: Presented in same order as in Section 4.3

Shear Modulus

Specimen h (in) b (in) Gauge Length (in) Avg Slope (in-lb/rad) G (psi)

M-10-4-1 1.515 7.301 32.0 40924 1.78E+05M-10-4-2 1.512 7.296 32.0 28888 1.26E+05M-10-4-3 1.510 7.286 32.0 31189 1.37E+05M-10-4-4 1.513 7.258 32.0 47792 2.10E+05M-10-4-5 1.518 7.287 32.0 38923 1.69E+05M-10-4-6 1.521 7.292 32.0 48867 2.11E+05M-10-4-7 1.502 7.264 32.0 27434 1.23E+05M-10-4-8 1.513 7.284 32.0 49861 2.18E+05M-10-4-9 1.516 7.244 32.0 31798 1.39E+05M-10-4-10 1.515 7.294 32.0 33226 1.45E+05

Avg 1.513 7.281 32 37890 1.66E+05St Dev 0.005 0.019 0 8604 3.68E+04COV 0.3% 0.3% 0.0% 22.7% 22.2%

Specimen h (in) b (in) Gauge Length (in) Avg Slope (in-lb/rad) G (psi)

L-10-4-1 1.646 7.234 32.0 28389 9.86E+04L-10-4-2 1.573 7.223 32.0 29414 1.16E+05L-10-4-3 1.557 7.208 32.0 24444 9.98E+04L-10-4-4 1.614 7.182 32.0 24970 9.25E+04L-10-4-5 1.500 7.240 32.0 21976 9.93E+04L-10-4-6 1.522 7.241 32.0 21807 9.45E+04L-10-4-7 1.521 7.249 32.0 23819 1.03E+05L-10-4-8 1.570 7.225 32.0 25029 9.96E+04L-10-4-9 1.563 7.248 32.0 26807 1.08E+05L-10-4-10 1.577 7.235 32.0 33103 1.30E+05

Avg 1.564 7.229 32.0 25976 1.04E+05St Dev 0.044 0.021 0.0 3518 1.13E+04COV 2.8% 0.3% 0.0% 13.5% 10.8%

Shear Modulus Test Data: MSR

ASTM D 198 Torsion

Shear Modulus Test Data: LVL

ASTM D 198 Torsion

Appendix E 159

Specimen h (in) b (in) Gauge Length (in) Avg Slope (in-lb/rad)

G (psi)

P-10-4-1 1.512 7.336 32.0 20777 9.04E+04P-10-4-2 1.519 7.408 32.0 23807 1.01E+05P-10-4-3 1.517 7.380 32.0 22697 9.72E+04P-10-4-4 1.495 7.360 32.0 22086 9.89E+04P-10-4-5 1.526 7.396 32.0 23455 9.85E+04P-10-4-6 1.508 7.259 32.0 23662 1.05E+05P-10-4-7 1.486 7.335 32.0 21667 9.90E+04P-10-4-8 1.509 7.417 32.0 23536 1.02E+05P-10-4-9 1.478 7.242 32.0 19655 9.26E+04

P-10-4-10 1.519 7.364 32.0 22994 9.83E+04Avg 1.507 7.350 32.0 22434 9.83E+04

St Dev 0.016 0.059 0.0 1383 4.23E+03COV 1.0% 0.8% 0.0% 6.2% 4.3%

Shear Modulus Test Data: PSL

ASTM D 198 Torsion

Appendix E 160

Shear Modulus Test Data: MSR ASTM D 198 Torsion Torque-Rotation Curve

Shear Modulus Test Data: LVL ASTM D 198 Torsion Torque-Rotation Curve

Shear Modulus Test Data: PSLASTM D 198 Torsion Torque-Rotation Curve

M-10-4-1

y = 40941x + 53.355R2 = 0.9963

0100200300400500600700800

0.000 0.004 0.008 0.012 0.016 0.020

Rotation (rad)

Torq

ue (i

n-lb

)

L-10-4-1

y = 28180x + 27.732R2 = 0.9956

0100200300400500600700800

0.000 0.004 0.008 0.012 0.016 0.020

Rotation (rad)

Torq

ue (i

n-lb

)

P-10-4-1

y = 20048x + 14.525R2 = 0.9954

0100200300400500600700800

0.000 0.004 0.008 0.012 0.016 0.020

Rotation (rad)

Torq

ue (i

n-lb

)

Appendix E 161


Specimen b (in) h (in) I (in4) L (in) Avg Slope (lb/in) Ef (psi) G (psi) E (psi)M-10-4-1 1.515 7.301 49.134 64.0 13605 1.51E+06 1.78E+05 1.74E+06M-10-4-2 1.512 7.296 48.939 64.0 14850 1.66E+06 1.26E+05 2.08E+06M-10-4-3 1.510 7.286 48.670 64.0 10322 1.16E+06 1.37E+05 1.33E+06M-10-4-4 1.513 7.258 48.207 64.0 15072 1.71E+06 2.10E+05 1.95E+06M-10-4-5 1.518 7.287 48.948 64.0 16485 1.84E+06 1.69E+05 2.21E+06M-10-4-6 1.521 7.292 49.146 64.0 14331 1.59E+06 2.11E+05 1.81E+06M-10-4-7 1.502 7.264 47.975 64.0 11579 1.32E+06 1.23E+05 1.58E+06M-10-4-8 1.513 7.284 48.727 64.0 12745 1.43E+06 2.18E+05 1.59E+06M-10-4-9 1.516 7.244 48.023 64.0 15875 1.81E+06 1.39E+05 2.25E+06

M-10-4-10 1.515 7.294 48.987 64.0 17413 1.94E+06 1.45E+05 2.45E+06

Avg 1.513 7.281 48.676 64 14228 1.60E+06 1.66E+05 1.90E+06

St Dev 0.005 0.019 0.448 0 2209 2.45E+05 3.68E+04 3.53E+05

COV 0.3% 0.3% 0.9% 0.0% 15.5% 15.4% 22.2% 18.6%

Specimen b (in) h (in) I (in4) L (in) Avg Slope (lb/in) Ef (psi) G (psi) E (psi)L-10-4-1 1.646 7.234 51.926 64.0 13889 1.46E+06 9.86E+04 1.89E+06L-10-4-2 1.573 7.223 49.406 64.0 16080 1.78E+06 1.16E+05 2.32E+06L-10-4-3 1.557 7.208 48.591 64.0 15578 1.75E+06 9.98E+04 2.39E+06L-10-4-4 1.614 7.182 49.826 64.0 15285 1.68E+06 9.25E+04 2.31E+06L-10-4-5 1.500 7.240 47.438 64.0 16336 1.88E+06 9.93E+04 2.65E+06L-10-4-6 1.522 7.241 48.169 64.0 15558 1.76E+06 9.45E+04 2.47E+06L-10-4-7 1.521 7.249 48.278 64.0 15435 1.75E+06 1.03E+05 2.36E+06L-10-4-8 1.570 7.225 49.328 64.0 16366 1.81E+06 9.96E+04 2.51E+06L-10-4-9 1.563 7.248 49.600 64.0 14587 1.61E+06 1.08E+05 2.09E+06

L-10-4-10 1.577 7.235 49.776 64.0 16756 1.84E+06 1.30E+05 2.35E+06Avg 1.564 7.229 49.234 64.0 15587 1.73E+06 1.04E+05 2.33E+06

St Dev 0.044 0.021 1.236 0.0 868 1.23E+05 1.13E+04 2.15E+05COV 2.8% 0.3% 2.5% 0.0% 5.6% 7.1% 10.8% 9.2%

ASTM D 198 Three-Point BendingModulus of Elasticity Test Data: MSR

Modulus of Elasticity Test Data: LVLASTM D 198 Three-Point Bending

Appendix E 162

Specimen b (in) h (in) I (in4) L (in) Avg Slope (lb/in) Ef (psi) G (psi) E (psi)P-10-4-1 1.512 7.336 49.745 64.0 16462 1.81E+06 9.04E+04 2.64E+06P-10-4-2 1.519 7.408 51.461 64.0 13509 1.43E+06 1.01E+05 1.86E+06P-10-4-3 1.517 7.380 50.813 64.0 15166 1.63E+06 9.72E+04 2.23E+06P-10-4-4 1.495 7.360 49.670 64.0 14201 1.56E+06 9.89E+04 2.08E+06P-10-4-5 1.526 7.396 51.447 64.0 14824 1.57E+06 9.85E+04 2.12E+06P-10-4-6 1.508 7.259 48.073 64.0 12510 1.42E+06 1.05E+05 1.80E+06P-10-4-7 1.486 7.335 48.869 64.0 14340 1.60E+06 9.90E+04 2.15E+06P-10-4-8 1.509 7.417 51.305 64.0 15177 1.62E+06 1.02E+05 2.17E+06P-10-4-9 1.478 7.242 46.793 64.0 16451 1.92E+06 9.26E+04 2.82E+06

P-10-4-10 1.519 7.364 50.539 64.0 15472 1.67E+06 9.83E+04 2.29E+06

Avg 1.507 7.350 49.872 64.0 14811 1.62E+06 9.83E+04 2.21E+06

St Dev 0.016 0.059 1.569 0.0 1234 1.52E+05 4.23E+03 3.14E+05

COV 1.0% 0.8% 3.1% 0.0% 8.3% 9.4% 4.3% 14.2%

ASTM D 198 Three-Point BendingModulus of Elasticity Test Data: PSL

Appendix E 163

Modulus of Elasticity Test Data: MSR ASTM D 198 Three-point Bending Load-Displacement Curve

Modulus of Elasticity Test Data: LVLASTM D 198 Three-point Bending Load-Displacement Curve

Modulus of Elasticity Test Data: PSL ASTM D 198 Three-point Bending Load-Displacement Curve

M-10-4-1 - Trial 1

y = 13605x + 44.616R2 = 0.9983

0200400600800

1000120014001600

0.00 0.02 0.04 0.06 0.08 0.10 0.12

Displacement (in)

Load

(lb)

L-10-4-1 - Trial 1

y = 13661x + 45.873R2 = 0.9991

0200400600800

1000120014001600

0.00 0.02 0.04 0.06 0.08 0.10 0.12

Displacement (in)

Load

(lb)

P-10-4-1 0 Trial 1

y = 16044x + 22.898R2 = 0.9982

0200400600800

1000120014001600

0.00 0.02 0.04 0.06 0.08 0.10 0.12

Displacement (in)

Load

(lb)

Appendix E 164

Specimen Thickness (in) Load (lbs) Embedment Strength (psi) Displacement (in) Load (lbs) Embedment

Strength (psi)Displacement

(in)M-10-4-1 1.503 3314 4411 0.111 4861 6471 0.350M-10-4-2 1.496 2024 2706 0.090 2821 3771 0.439M-10-4-3 1.505 1754 2332 0.079 3445 4580 0.559M-10-4-4 1.496 3469 4639 0.098 4942 6609 0.390M-10-4-5 1.515 3056 4034 0.104 4976 6569 0.486M-10-4-6 1.520 3692 4858 0.099 5563 7320 0.461M-10-4-7 1.485 2022 2723 0.087 2877 3875 0.519M-10-4-8 1.502 4933 6569 0.119 9000 11984 0.569M-10-4-91 1.497 2298 3071 0.085 4174 5578 0.750M-10-4-10 1.507 3506 4653 0.091 6187 8211 0.547M-5-4-11 1.469 1615 2200 0.075 4299 5855 0.750M-5-4-2 1.517 1728 2279 0.075 3821 5039 0.701M-5-4-31 1.508 3781 5016 0.089 7701 10217 0.750

M-5-4-41 1.518 1576 2077 0.063 5580 7354 0.750

M-5-4-51 1.497 2335 3120 0.080 6848 9149 0.750M-5-4-6 1.512 2101 2779 0.075 3801 5028 0.562M-5-7-1 1.523 3537 4645 0.096 5988 7863 0.430M-5-7-2 1.462 2021 2765 0.077 3402 4654 0.496M-5-7-3 1.489 3009 4042 0.092 5149 6916 0.521M-5-7-4 1.447 1486 2055 0.078 3639 5031 0.702M-5-7-5 1.504 4232 5630 0.097 6219 8273 0.359M-5-7-61 1.509 2210 2929 0.087 4896 6489 0.750M-5-10-1 1.509 3332 4416 0.096 5192 6881 0.361M-5-10-2 1.496 2785 3725 0.098 3828 5119 0.232M-5-10-3 1.509 2183 2894 0.086 2873 3809 0.208M-5-10-4 1.488 2048 2753 0.083 3888 5226 0.516M-5-10-5 1.495 3500 4682 0.094 6002 8029 0.652M-5-10-6 1.502 3152 4197 0.087 4516 6013 0.431M-3-4-11 1.493 2106 2822 0.087 3128 4192 0.750

M-3-4-21 1.503 2447 3256 0.075 7281 9689 0.750

M-3-4-31 1.504 2840 3778 0.085 8759 11651 0.750M-3-4-4 1.510 3631 4811 0.091 5743 7609 0.526M-3-4-51 1.490 1401 1881 0.073 4923 6608 0.750

M-3-4-61 1.488 1655 2225 0.074 4117 5535 0.750

M-0-4-11 1.490 2379 3193 0.074 6249 8388 0.750M-0-4-2 1.498 2373 3169 0.088 3443 4598 0.330M-0-4-3 1.487 2301 3095 0.085 3434 4619 0.387M-0-7-1 1.473 2470 3354 0.088 3817 5183 0.652M-0-7-2 1.499 2026 2703 0.092 4386 5852 0.738M-0-7-31 1.491 1934 2595 0.078 4582 6148 0.750

Mean 1.497 2607 3477 0.087 4909 6550 0.572Std. Dev 0.016 835 1099 0.011 1536 2027 0.167

COV (%) 1.0% 32.0% 31.6% 12.7% 31.3% 30.9% 29.3%

1 Capacity defined at displacement limit (0.75 in.)

5% Offset Yield Capacity

ASTM D 5764-97a - Full-hole SpecimensDowel Embedment Test Data: MSR

Appendix E 165



(in)L-10-4-1 1.617 2766 3421 0.104 3786 4683 0.302L-10-4-2 1.572 3010 3831 0.119 4468 5686 0.329L-10-4-3 1.570 3714 4733 0.130 5542 7062 0.445L-10-4-4 1.616 2943 3642 0.118 4829 5976 0.466L-10-4-5 1.503 2966 3947 0.118 4157 5532 0.336L-10-4-6 1.515 3118 4116 0.109 4464 5893 0.362L-10-4-7 1.544 3957 5127 0.116 5204 6743 0.284L-10-4-8 1.557 3552 4564 0.117 4750 6103 0.460L-10-4-9 1.572 3578 4552 0.110 4929 6271 0.254L-10-4-10 1.580 3947 4998 0.114 5483 6943 0.300

L-5-4-1 1.581 3528 4463 0.119 5855 7407 0.398L-5-4-2 1.576 3021 3835 0.139 3981 5054 0.345L-5-4-3 1.482 3310 4468 0.122 4191 5658 0.277L-5-4-4 1.497 3517 4699 0.110 4640 6199 0.275L-5-4-5 1.571 3182 4051 0.127 4613 5873 0.422L-5-4-6 1.571 3271 4166 0.118 3901 4968 0.216L-5-7-1 1.581 3480 4404 0.132 5280 6681 0.406L-5-7-2 1.573 3180 4043 0.106 5073 6450 0.415L-5-7-3 1.536 3319 4322 0.113 5228 6807 0.554L-5-7-4 1.548 2546 3290 0.096 3920 5066 0.332L-5-7-5 1.543 3433 4450 0.111 3888 5040 0.147L-5-7-6 1.571 3483 4436 0.123 4279 5449 0.209

L-5-10-1 1.569 3748 4778 0.114 4868 6205 0.262L-5-10-2 1.596 4182 5242 0.116 6069 7608 0.361L-5-10-3 1.567 3287 4195 0.109 4961 6332 0.311L-5-10-4 1.588 3582 4511 0.123 4337 5462 0.215L-5-10-5 1.561 3620 4638 0.108 4532 5807 0.421L-5-10-6 1.558 3289 4222 0.109 4661 5983 0.329L-3-4-1 1.512 3286 4347 0.114 3845 5086 0.201L-3-4-2 1.590 3831 4819 0.138 4051 5096 0.164L-3-4-3 1.508 3935 5219 0.123 5004 6637 0.245L-3-4-4 1.608 3866 4808 0.133 4888 6080 0.284L-3-4-5 1.596 3921 4914 0.127 4686 5872 0.195L-3-4-6 1.607 3000 3734 0.110 4434 5518 0.265L-0-4-1 1.591 3627 4559 0.113 4034 5071 0.173L-0-4-2 1.512 3054 4040 0.114 4459 5898 0.367L-0-4-3 1.556 3648 4689 0.121 5113 6572 0.362L-0-7-1 1.607 3798 4728 0.121 4987 6209 0.270L-0-7-2 1.625 3170 3902 0.112 3994 4916 0.322L-0-7-3 1.610 3432 4263 0.109 4695 5832 0.266

Mean 1.566 3427 4379 0.117 4652 5943 0.314Std. Dev 0.036 366 466 0.009 566 715 0.092

COV (%) 2.3% 10.7% 10.6% 7.9% 12.2% 12.0% 29.3%


ASTM D 5764-97a - Full-hole SpecimensDowel Embedment Test Data: LVL

Appendix E 166



(in)P-10-4-3 1.5205 2456 3231 0.093 4994 6569 0.498P-10-4-4 1.5135 1836 2426 0.100 3744 4947 0.609P-10-4-5 1.5300 2073 2710 0.093 6056 7916 0.605P-10-4-6 1.5130 2381 3147 0.102 4333 5728 0.556P-10-4-7 1.5110 2252 2981 0.100 4978 6589 0.728P-10-4-8 1.5145 2148 2837 0.096 3197 4222 0.462P-10-4-9 1.4545 2015 2771 0.105 3536 4862 0.650P-10-4-10 1.5080 2395 3176 0.100 4330 5743 0.586P-10-4-11 1.5115 3468 4589 0.131 5954 7878 0.584P-10-4-121 1.4990 2668 3560 0.104 4959 6616 0.750

P-5-4-11 1.5165 2272 2996 0.091 4790 6317 0.750P-5-4-2 1.5145 2444 3227 0.105 3901 5152 0.388P-5-4-3 1.5165 2434 3210 0.094 5251 6925 0.519P-5-4-4 1.5045 2474 3289 0.101 4468 5940 0.658P-5-4-5 1.5150 2200 2904 0.094 3169 4183 0.272P-5-4-6 1.5040 2818 3747 0.113 3795 5047 0.283P-5-7-1 1.5100 1926 2551 0.100 3693 4891 0.639P-5-7-2 1.4705 3067 4171 0.122 4442 6041 0.525P-5-7-3 1.5220 2029 2666 0.096 3370 4428 0.567P-5-7-4 1.5070 2799 3715 0.095 5357 7109 0.689P-5-7-5 1.5055 2362 3138 0.100 5071 6737 0.744P-5-7-6 1.5190 2178 2868 0.096 3786 4985 0.377

P-5-10-1 1.5070 2858 3793 0.104 4944 6561 0.589P-5-10-2 1.5060 3022 4013 0.110 5039 6692 0.504P-5-10-3 1.5070 2007 2664 0.113 3032 4024 0.421P-5-10-4 1.5200 2326 3061 0.091 4296 5653 0.568P-5-10-5 1.5175 3038 4004 0.115 5243 6910 0.415P-5-10-61 1.5200 2362 3108 0.100 5056 6653 0.750P-3-4-1 1.5030 2059 2740 0.090 3799 5055 0.574P-3-4-2 1.5145 2322 3066 0.103 4502 5945 0.645P-3-4-3 1.5125 2087 2760 0.101 3995 5283 0.469P-3-4-4 1.5115 1930 2554 0.092 5535 7324 0.679P-3-4-51 1.5095 1892 2507 0.090 5669 7511 0.750P-3-4-6 1.5090 1992 2640 0.087 4982 6603 0.746P-0-4-1 1.4925 2841 3807 0.109 5171 6929 0.638P-0-4-2 1.5185 2660 3503 0.097 5806 7647 0.599P-0-4-3 1.5260 2224 2915 0.106 3863 5063 0.534P-0-7-1 1.4900 2787 3741 0.099 4886 6558 0.571P-0-7-2 1.5030 3118 4149 0.119 5174 6885 0.444P-0-7-3 1.5220 2642 3472 0.100 4871 6401 0.365

Mean 1.509 2422 3210 0.101 4576 6063 0.568Std. Dev 0.014 397 535 0.009 805 1060 0.130

COV (%) 0.9% 16.4% 16.7% 9.2% 17.6% 17.5% 22.9%

1 Capacity defined at displacement limit (0.75 in.)


ASTM D 5764-97a - Full-hole SpecimensDowel Embedment Test Data: PSL

Appendix E 167

Dowel Embedment Test Data: MSRASTM D 5764-97a - Full-hole Specimens - Load-Displacement Curve with 5% Offset Analysis

Dowel Embedment Test Data: LVLASTM D 5764-97a - Full-hole Specimens - Load-Displacement Curve with 5% Offset Analysis

Dowel Embedment Test Data: PSLASTM D 5764-97a - Full-hole Specimens - Load-Displacement Curve with 5% Offset Analysis

DE Specimen M-10-4-1: Load vs. Displacement

0

1000

2000

3000

4000

5000

6000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Displacement (in.)

Load

(lbs

)

DE Specimen L-5-10-1: Load vs. Displacement

0

1000

2000

3000

4000

5000

6000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Displacement (in.)

Load

(lbs

)

DE Specimen P-5-10-2: Load vs. Displacement

0

1000

2000

3000

4000

5000

6000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Displacement (in.)

Load

(lbs

)

Test Data

5% Offset Line

Test Data

5% Offset Line

Test Data

5% Offset Line

Appendix E 168

ASTM D 5764-97a - Full-hole Specimens - Load-Displacement Curve

Dowel Embedment Test Data: Resistance increase at large displacements due to compaction behavior

DE Specimen M-0-4-1: Load vs. Displacement

0

2000

4000

6000

8000

10000

12000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Displacement (in.)

Load

(lbs

)

Displacement Limit0.75 in.

Test Data

5% Offset Line

Appendix E 169

Specimen ID Capacity (lbs) 5% Offset Yield (lbs)

Capacity Moment (in-lbs)

5% Offset Yield Moment (in-lbs)

Capacity Strength (psi)

5% Offset Yield Strength (psi)

1 685 606 1713 1515 82200 727202 793 679 1983 1698 95160 814803 701 582 1753 1455 84120 698404 695 575 1738 1438 83400 690005 767 654 1918 1635 92040 784806 684 592 1710 1480 82080 710407 670 562 1675 1405 80400 674408 679 550 1698 1375 81480 660009 779 642 1948 1605 93480 77040

10 678 571 1695 1428 81360 68520

Mean 713 601 1783 1503 85572 72156Std Dev 47 43 118 108 5656 5175

COV 0.066 0.072 0.066 0.072 0.066 0.072

Bolt Bending Strength Test DataASTM F 1575-03 Cantilever Method - Load-Displacement Curve

ASTM F 1575-03 Cantilever MethodBolt Bending Strength Test Data

Specimen 1: Load vs. Displacement

0

200

400

600

800

1000

0 0.2 0.4 0.6 0.8 1

Displacement (in.)

Loa

d (lb

s)

Test Data

5% Offset Line

Appendix E 170

Connection Number Length (in) Width (in) Max Load (lb) Tensile Strength (psi)

M-10-4-1 1.502 0.924 504.2 363M-10-4-2 1.495 0.921 452.3 329M-10-4-3 1.506 0.925 337.5 242M-10-4-4 1.498 0.925 648.7 468M-10-4-5 1.521 0.919 546.8 391M-10-4-6 1.528 0.939 684.0 477M-10-4-7 1.495 0.922 262.4 190M-10-4-8 1.507 0.933 565.2 402M-10-4-9 1.488 0.912 574.8 424

M-10-4-10 1.499 0.914 542.8 396M-5-4-1 1.479 0.954 320.0 227M-5-4-2 1.493 0.956 515.0 361M-5-4-3 1.511 0.954 491.7 341M-5-4-4 1.489 0.972 353.3 244M-5-4-5 1.533 0.947 694.5 479M-5-4-6 1.486 0.947 234.1 166M-5-7-1 1.508 0.929 496.3 354M-5-7-2 1.480 0.943 385.9 277M-5-7-3 1.497 0.923 255.2 185M-5-7-4 1.469 0.946 295.2 213M-5-7-5 1.509 0.950 310.5 217M-5-7-6 1.512 0.928 495.2 353M-5-10-1 1.509 1.016 382.7 250M-5-10-2 1.493 0.974 312.9 215M-5-10-3 1.511 0.932 266.0 189M-5-10-4 1.487 0.944 382.5 273M-5-10-5 1.501 0.935 454.1 324M-5-10-6 1.509 0.955 447.0 310M-3-4-1 1.497 0.946 369.4 261M-3-4-2 1.510 0.939 382.4 270M-3-4-3 1.508 0.931 663.4 473M-3-4-4 1.496 0.930 541.8 390M-3-4-5 1.498 0.913 439.6 322M-3-4-6 1.495 0.922 576.2 418M-0-4-1 1.484 0.936 589.7 425M-0-4-2 1.505 0.918 536.8 389M-0-4-3 1.500 0.920 487.8 354M-0-7-1 1.497 0.918 351.2 256M-0-7-2 1.489 0.949 615.7 436M-0-7-3 1.515 0.915 582.1 420Mean 1.500 0.937 458.7 327St Dev 0.013 0.020 128.4 92

COV (%) 0.9% 2.2% 28.0% 28.2%

ASTM D 143Tension perpendicular to grain test data: MSR

Appendix E 171

Connection Number Length (in) Width (in) Max Load (lb) Tensile Strength (psi)

L-10-4-1 1.639 0.920 191.9 127L-10-4-2 1.589 0.923 197.8 135L-10-4-3 1.549 0.928 116.4 81L-10-4-4 1.626 0.943 206.9 135L-10-4-5 1.505 0.928 199.8 143L-10-4-6 1.514 0.931 150.4 107L-10-4-7 1.526 0.912 112.6 81L-10-4-8 1.554 0.951 131.0 89L-10-4-9 1.561 0.931 181.6 125L-10-4-10 1.588 0.943 162.7 109

L-5-4-1 1.551 0.926 226.2 158L-5-4-2 1.520 0.925 145.9 104L-5-4-3 1.504 0.914 195.8 142L-5-4-4 1.548 0.929 178.4 124L-5-4-5 1.581 0.953 155.5 103L-5-4-6 1.580 0.922 117.4 81L-5-7-1 1.596 0.917 185.1 127L-5-7-2 1.601 0.939 145.1 97L-5-7-3 1.537 0.943 131.8 91L-5-7-4 1.563 0.939 126.9 86L-5-7-5 1.533 0.935 226.8 158L-5-7-6 1.583 0.939 66.6 45

L-5-10-1 1.582 0.943 209.2 140L-5-10-2 1.602 0.939 105.4 70L-5-10-3 1.558 0.894 178.7 128L-5-10-4 1.597 0.914 111.9 77L-5-10-5 1.590 0.936 220.6 148L-5-10-6 1.547 0.875 211.6 156L-3-4-1 1.508 0.930 195.1 139L-3-4-2 1.586 0.940 127.0 85L-3-4-3 1.536 0.946 180.3 124L-3-4-4 1.599 0.934 113.8 76L-3-4-5 1.598 0.916 132.4 90L-3-4-6 1.629 0.935 169.7 112L-0-4-1 1.609 0.910 171.2 117L-0-4-2 1.540 0.902 150.4 108L-0-4-3 1.575 0.936 196.4 133L-0-7-1 1.616 0.918 113.2 76L-0-7-2 1.612 0.927 96.4 65L-0-7-3 1.627 0.918 151.9 102Mean 1.571 0.927 159.7 110St Dev 0.037 0.016 40.4 29

COV (%) 2.4% 1.7% 25.3% 26.1%

Tension perpendicular to grain test data: LVLASTM D 143

Appendix E 172

Connection Number Length (in) Width (in) Max Load (lb) Tensile Strength (psi)P-10-4-3 1.529 0.925 252.9 179P-10-4-4 1.513 0.902 234.2 172P-10-4-5 1.530 0.941 116.8 81P-10-4-6 1.522 0.942 279.6 195P-10-4-7 1.510 0.914 173.1 125P-10-4-8 1.476 0.910 157.4 117P-10-4-9 1.385 0.903 113.7 91

P-10-4-10 1.521 0.957 220.4 151P-10-4-11 1.517 0.939 197.6 139P-10-4-12 1.512 0.921 234.4 168

P-5-4-1 1.521 0.920 76.9 55P-5-4-2 1.519 0.945 320.0 223P-5-4-3 1.520 0.918 269.8 193P-5-4-4 1.503 0.927 136.6 98P-5-4-5 1.521 0.947 208.7 145P-5-4-6 1.496 0.943 238.3 169P-5-7-1 1.519 0.907 263.4 191P-5-7-2 1.492 0.946 265.1 188P-5-7-3 1.519 0.940 255.7 179P-5-7-4 1.505 0.958 187.5 130P-5-7-5 1.512 0.948 116.7 81P-5-7-6 1.525 0.926 272.4 193

P-5-10-1 1.517 0.938 189.6 133P-5-10-2 1.516 0.940 281.9 198P-5-10-3 1.533 0.946 275.7 190P-5-10-4 1.532 0.917 72.5 52P-5-10-5 1.519 0.920 176.8 127P-5-10-6 1.519 0.939 97.3 68P-3-4-1 1.525 0.905 272.1 197P-3-4-2 1.526 0.927 218.9 155P-3-4-3 1.519 0.901 213.1 156P-3-4-4 1.497 0.914 183.4 134P-3-4-5 1.512 0.903 92.1 68P-3-4-6 1.512 0.933 192.7 137P-0-4-1 1.490 0.937 236.4 169P-0-4-2 1.503 0.904 247.6 182P-0-4-3 1.531 0.944 218.1 151P-0-7-1 1.508 0.933 354.7 252P-0-7-2 1.484 0.907 161.0 120P-0-7-3 1.514 0.927 160.2 114Mean 1.510 0.928 205.9 147St Dev 0.024 0.017 67.9 48

COV (%) 1.6% 1.8% 33.0% 32.4%

Tension perpendicular to grain test data: PSL

ASTM D 143

Appendix E 173

Tension perpendicular to grain test data: MSRASTM D 143 - Load Displacement Curve

Tension perpendicular to grain test data: LVLASTM D 143 - Load Displacement Curve

Tension perpendicular to grain test data: PSLASTM D 143 - Load Displacement Curve

Tension Perp Load vs. Displacement - Specimen M-10-4-1

0

100

200

300

400

500

600

0 0.02 0.04 0.06 0.08 0.1 0.12

Crosshead Displacement (in)

Load

(lb)

Tension Perp Load vs. Displacement - Specimen L-10-4-2

0

100

200

300

400

500

600

0 0.02 0.04 0.06 0.08 0.1 0.12


Load

(lb)

Tension Perp Load vs. Displacement - Specimen P-10-4-3

0

100

200

300

400

500

600

0 0.02 0.04 0.06 0.08 0.1 0.12


Load

(lb)

Appendix E 174

Specimen Thickness (in) Crack Length (in) Peak (lb) W (lb-in) GIf (lb-in/in2)

M-10-4-1 1.496 3.362 207.7 23.76 4.73M-10-4-2 1.499 3.364 204.3 23.18 4.60M-10-4-3 1.498 3.293 163.8 16.62 3.37M-10-4-4 1.498 3.498 226.1 36.40 6.95M-10-4-5 1.523 3.454 210.6 27.86 5.30M-10-4-6 1.528 3.373 244.7 32.66 6.34M-10-4-7 1.482 3.383 157.2 10.70 2.14M-10-4-8 1.508 3.106 252.7 45.05 9.62M-10-4-9 1.500 3.650 210.9 22.49 4.11M-10-4-10 1.509 3.435 198.1 20.00 3.86M-5-4-1 1.467 3.322 104.0 7.38 1.51M-5-4-2 1.488 3.176 148.4 8.75 1.85M-5-4-3 1.505 3.384 238.9 36.95 7.26M-5-4-4 1.485 3.451 124.6 10.34 2.02M-5-4-5 1.519 3.467 112.7 29.15 5.53M-5-4-6 1.515 3.551 115.7 13.20 2.45M-5-7-1 1.513 3.402 237.3 30.75 5.98M-5-7-2 1.476 3.255 115.8 9.70 2.02M-5-7-3 1.493 3.444 226.8 22.82 4.44M-5-7-4 1.475 3.650 141.0 13.77 2.56M-5-7-5 1.501 3.303 258.8 22.11 4.46M-5-7-6 1.520 3.521 179.3 32.21 6.02

M-5-10-1 1.498 3.367 200.1 17.93 3.55M-5-10-2 1.513 3.282 173.4 25.15 5.06M-5-10-3 1.494 3.378 221.7 22.73 4.51M-5-10-4 1.512 3.252 205.1 21.80 4.43M-5-10-5 1.478 3.430 257.1 33.94 6.70M-5-10-6 1.507 3.412 202.1 24.54 4.77M-3-4-1 1.491 3.170 154.1 10.12 2.14M-3-4-2 1.499 3.465 198.3 48.09 9.26M-3-4-3 1.486 3.507 201.4 45.86 8.80M-3-4-4 1.505 3.402 249.7 28.51 5.57M-3-4-5 1.510 3.089 135.0 6.61 1.42M-3-4-6 1.486 3.093 131.8 8.64 1.88M-0-4-1 1.464 3.337 196.1 16.57 3.39M-0-4-2 1.497 3.215 168.7 14.42 3.00M-0-4-3 1.503 3.235 202.7 20.29 4.17M-0-7-1 1.489 3.222 188.4 15.61 3.25M-0-7-2 1.505 3.200 175.5 15.23 3.16M-0-7-3 1.492 3.217 162.7 13.30 2.77Mean 1.498 3.353 187.58 22.13 4.37St Dev 0.015 0.139 43.61 10.87 2.10COV 1.0% 4.1% 23.2% 49.1% 48.1%

Mode I Fracture Energy Test Data: MSRCompact Tension (CT) Specimens

Appendix E 175


L-10-4-1 1.619 3.650 176.5 75.68 12.81L-10-4-2 1.564 3.650 162.6 39.54 6.93L-10-4-3 1.535 3.650 169.2 39.08 6.98L-10-4-4 1.636 3.650 207.4 70.50 11.81L-10-4-5 1.493 3.650 170.4 42.33 7.77L-10-4-6 1.517 3.650 212.5 64.01 11.56L-10-4-7 1.515 3.650 195.5 47.12 8.52L-10-4-8 1.550 3.650 179.8 42.44 7.50L-10-4-9 1.548 3.650 189.4 45.05 7.98

L-10-4-10 1.575 3.650 164.8 31.73 5.52L-5-4-1 1.594 3.650 212.3 47.41 8.15L-5-4-2 1.519 3.650 167.5 36.96 6.67L-5-4-3 1.492 3.650 212.6 65.60 12.05L-5-4-4 1.514 3.650 178.4 44.29 8.01L-5-4-5 1.573 3.650 156.8 35.58 6.20L-5-4-6 1.539 3.650 186.3 49.56 8.83L-5-7-1 1.591 3.650 177.8 45.07 7.76L-5-7-2 1.591 3.650 215.7 44.56 7.68L-5-7-3 1.554 3.650 195.6 28.30 4.99L-5-7-4 1.550 3.650 151.8 22.90 4.05L-5-7-5 1.516 3.650 207.1 51.08 9.23L-5-7-6 1.574 3.650 172.4 49.74 8.66L-5-10-1 1.567 3.650 171.6 42.50 7.43L-5-10-2 1.591 3.650 147.1 32.15 5.54L-5-10-3 1.583 3.650 165.5 31.04 5.37L-5-10-4 1.597 3.650 156.9 37.71 6.47L-5-10-5 1.561 3.650 207.1 38.95 6.84L-5-10-6 1.557 3.650 180.3 49.81 8.77L-3-4-1 1.495 3.650 217.5 53.36 9.78L-3-4-2 1.595 3.650 152.8 39.80 6.84L-3-4-3 1.522 3.650 168.4 47.64 8.58L-3-4-4 1.596 3.650 153.5 31.48 5.41L-3-4-5 1.584 3.650 153.8 44.12 7.63L-3-4-6 1.608 3.650 182.0 41.57 7.08L-0-4-1 1.593 3.650 173.0 41.86 7.20L-0-4-2 1.516 3.650 158.3 25.57 4.62L-0-4-3 1.569 3.650 176.5 32.96 5.76L-0-7-1 1.606 3.650 183.5 42.73 7.29L-0-7-2 1.606 3.650 190.5 48.02 8.19L-0-7-3 1.625 3.650 176.1 37.03 6.24Mean 1.563 3.650 179.4 43.42 7.62St Dev 0.039 0.000 20.1 11.25 1.98COV 2.5% 0.0% 11.2% 25.9% 26.0%

Mode I Fracture Energy Test Data: LVLCompact Tension (CT) Specimens

Appendix E 176


P-10-4-3 1.515 3.650 212.0 64.47 11.66P-10-4-4 1.503 3.650 148.9 38.39 7.00P-10-4-5 1.523 3.650 201.8 54.42 9.79P-10-4-6 1.512 3.650 267.9 79.83 14.47P-10-4-7 1.510 3.650 166.6 54.47 9.88P-10-4-8 1.505 3.650 191.5 40.65 7.40P-10-4-9 1.465 3.650 269.8 113.00 21.14P-10-4-10 1.500 3.650 238.7 65.18 11.91P-10-4-11 1.516 3.650 289.9 82.93 14.99P-10-4-12 1.469 3.650 284.5 78.89 14.72P-5-4-1 1.529 3.650 228.9 74.58 13.37P-5-4-2 1.528 3.650 211.4 78.56 14.09P-5-4-3 1.516 3.650 231.5 64.21 11.60P-5-4-4 1.526 3.650 234.7 83.36 14.97P-5-4-5 1.513 3.650 165.2 47.18 8.54P-5-4-6 1.511 3.650 255.0 120.02 21.77P-5-7-1 1.514 3.650 275.1 83.86 15.18P-5-7-2 1.466 3.650 297.4 95.80 17.90P-5-7-3 1.514 3.650 58.4 77.69 14.06P-5-7-4 1.510 3.650 273.8 67.69 12.28P-5-7-5 1.513 3.650 255.0 89.05 16.13P-5-7-6 1.518 3.650 155.3 51.27 9.25

P-5-10-1 1.509 3.650 159.7 50.23 9.12P-5-10-2 1.505 3.650 282.1 108.63 19.78P-5-10-3 1.519 3.650 197.1 63.09 11.38P-5-10-4 1.520 3.650 204.7 60.20 10.85P-5-10-5 1.520 3.650 232.0 70.78 12.76P-5-10-6 1.517 3.650 203.9 88.42 15.97P-3-4-1 1.532 3.650 222.8 76.13 13.61P-3-4-2 1.513 3.650 267.0 87.98 15.94P-3-4-3 1.510 3.650 241.3 89.55 16.25P-3-4-4 1.512 3.650 254.4 68.41 12.40P-3-4-5 1.511 3.650 298.8 119.56 21.69P-3-4-6 1.509 3.650 179.5 30.47 5.53P-0-4-1 1.517 3.650 247.5 131.59 23.77P-0-4-2 1.522 3.650 294.2 105.53 19.00P-0-4-3 1.510 3.650 240.4 57.10 10.36P-0-7-1 1.514 3.650 224.4 97.38 17.62P-0-7-2 1.510 3.650 215.9 73.35 13.31P-0-7-3 1.521 3.650 371.1 143.57 25.87Mean 1.511 3.650 231.3 78.19 14.18St Dev 0.015 0.000 54.6 25.52 4.65COV 1.0% 0.0% 23.6% 32.6% 32.8%

Mode I Fracture Energy Test Data: PSLCompact Tension (CT) Specimens

Appendix E 177

Mode I Fracture Energy: MSRCT Specimen - Load Displacement Curve

Mode I Fracture Energy: LVLCT Specimen - Load Displacement Curve

Mode I Fracture Energy: PSLCT Specimen - Load Displacement Curve

Load vs. Displacement - Specimen M-10-4-1

0

50

100

150

200

250

0.0 0.2 0.4 0.6 0.8 1.0

Displacement (in)

Load

(lb)

Load vs. Displacement - Specimen L-10-4-9

0

50

100

150

200

250

0.0 0.2 0.4 0.6 0.8 1.0

Displacement (in)

Load

(lb)

Load vs. Displacement - Specimen P-10-4-10

0

50

100

150

200

250

0.0 0.2 0.4 0.6 0.8 1.0

Displacement (in)

Load

(lb)

Appendix E 178

Specimen Wet Weight (g) Dry Weight (g) Volume (cm3) MC (%) SG

M-10-4-1 12.85 11.60 20.13 10.8% 0.58M-10-4-2 11.09 9.99 19.41 11.0% 0.51M-10-4-3 12.00 10.87 25.41 10.4% 0.43M-10-4-4 18.21 16.31 24.30 11.6% 0.67M-10-4-5 17.41 15.58 26.83 11.7% 0.58M-10-4-6 17.22 15.67 24.01 9.9% 0.65M-10-4-7 12.34 11.10 24.40 11.2% 0.45M-10-4-8 20.54 18.65 26.99 10.1% 0.69M-10-4-9 14.94 13.29 23.34 12.4% 0.57

M-10-4-10 15.62 14.13 23.96 10.5% 0.59M-5-4-1 13.22 11.68 24.75 13.2% 0.47M-5-4-2 13.74 12.11 22.69 13.5% 0.53M-5-4-3 17.43 15.59 23.44 11.8% 0.67M-5-4-4 14.44 12.66 23.64 14.1% 0.54M-5-4-5 15.58 13.93 25.01 11.8% 0.56M-5-4-6 10.25 9.20 21.81 11.4% 0.42M-5-7-1 17.57 15.52 25.35 13.2% 0.61M-5-7-2 11.21 10.04 23.35 11.7% 0.43M-5-7-3 13.99 12.53 21.56 11.7% 0.58M-5-7-4 14.84 13.29 25.68 11.7% 0.52M-5-7-5 17.34 15.69 24.39 10.5% 0.64M-5-7-6 17.21 15.39 25.05 11.8% 0.61M-5-10-1 17.29 15.57 26.10 11.0% 0.60M-5-10-2 13.61 12.35 23.54 10.2% 0.52M-5-10-3 14.30 12.89 26.58 10.9% 0.48M-5-10-4 17.20 15.08 25.23 14.1% 0.60M-5-10-5 18.27 16.38 26.23 11.5% 0.62M-5-10-6 16.76 14.89 25.32 12.6% 0.59M-3-4-1 11.91 10.61 21.89 12.3% 0.48M-3-4-2 14.21 12.58 22.21 13.0% 0.57M-3-4-3 18.57 16.45 24.61 12.9% 0.67M-3-4-4 17.47 15.66 25.28 11.6% 0.62M-3-4-5 14.33 12.66 24.49 13.2% 0.52M-3-4-6 10.77 9.54 24.23 12.9% 0.39M-0-4-1 14.91 13.12 23.56 13.6% 0.56M-0-4-2 15.73 13.85 26.06 13.6% 0.53M-0-4-3 15.10 13.38 24.37 12.9% 0.55M-0-7-1 13.10 11.73 22.43 11.7% 0.52M-0-7-2 14.85 13.30 25.15 11.7% 0.53M-0-7-3 14.71 13.08 23.66 12.5% 0.55Mean 15.05 13.45 24.16 11.9% 0.56St Dev 2.44 2.20 1.71 1.1% 0.07

COV (%) 16.2% 16.3% 7.1% 9.4% 13.2%

Moisture Content and Specific Gravity Results: MSR

Appendix E 179


L-10-4-1 16.62 15.13 24.68 9.8% 0.61L-10-4-2 18.30 16.74 26.50 9.3% 0.63L-10-4-3 19.35 17.69 24.56 9.4% 0.72L-10-4-4 17.43 15.75 25.70 10.7% 0.61L-10-4-5 16.80 15.38 23.33 9.2% 0.66L-10-4-6 17.40 15.93 24.18 9.2% 0.66L-10-4-7 16.32 14.95 23.39 9.2% 0.64L-10-4-8 18.96 17.31 26.65 9.5% 0.65L-10-4-9 16.14 14.81 22.10 9.0% 0.67L-10-4-10 16.20 14.91 21.84 8.7% 0.68

L-5-4-1 18.60 17.02 25.72 9.3% 0.66L-5-4-2 18.53 16.92 26.84 9.5% 0.63L-5-4-3 16.15 14.74 22.33 9.6% 0.66L-5-4-4 17.91 16.36 24.92 9.5% 0.66L-5-4-5 17.75 16.21 26.26 9.5% 0.62L-5-4-6 18.07 16.49 26.24 9.6% 0.63L-5-7-1 18.30 16.72 26.92 9.4% 0.62L-5-7-2 17.71 16.21 26.05 9.3% 0.62L-5-7-3 11.23 10.26 17.17 9.5% 0.60L-5-7-4 17.97 16.43 25.70 9.4% 0.64L-5-7-5 16.40 15.02 23.89 9.2% 0.63L-5-7-6 14.90 13.61 22.45 9.5% 0.61

L-5-10-1 18.89 17.25 26.40 9.5% 0.65L-5-10-2 18.10 16.49 25.95 9.8% 0.64L-5-10-3 18.16 16.57 26.27 9.6% 0.63L-5-10-4 17.69 16.11 26.32 9.8% 0.61L-5-10-5 19.84 18.17 27.84 9.2% 0.65L-5-10-6 16.70 15.21 23.98 9.8% 0.63L-3-4-1 17.18 15.66 23.86 9.7% 0.66L-3-4-2 20.08 18.30 27.88 9.7% 0.66L-3-4-3 18.29 16.65 24.23 9.8% 0.69L-3-4-4 17.81 16.15 24.80 10.3% 0.65L-3-4-5 19.44 17.76 27.49 9.5% 0.65L-3-4-6 19.32 17.61 28.57 9.7% 0.62L-0-4-1 20.40 18.55 28.90 10.0% 0.64L-0-4-2 18.64 16.94 25.80 10.0% 0.66L-0-4-3 18.69 17.01 27.15 9.9% 0.63L-0-7-1 22.71 20.60 30.25 10.2% 0.68L-0-7-2 20.01 18.14 27.37 10.3% 0.66L-0-7-3 16.39 14.86 26.10 10.3% 0.57Mean 17.88 16.32 25.41 9.6% 0.64St Dev 1.82 1.64 2.33 0.4% 0.03

COV (%) 10.2% 10.0% 9.2% 4.2% 4.3%

Moisture Content and Specific Gravity Results: LVL

Appendix E 180


P-10-4-3 17.42 16.04 24.94 8.6% 0.64P-10-4-4 16.27 14.95 24.70 8.8% 0.61P-10-4-5 17.44 16.02 25.26 8.9% 0.63P-10-4-6 16.78 15.37 24.00 9.2% 0.64P-10-4-7 13.92 12.73 20.80 9.3% 0.61P-10-4-8 15.44 14.19 22.92 8.8% 0.62P-10-4-9 15.52 14.01 21.81 10.8% 0.64P-10-4-10 14.32 13.13 21.46 9.1% 0.61P-10-4-11 16.39 15.03 22.94 9.0% 0.66P-10-4-12 18.62 17.10 25.56 8.9% 0.67

P-5-4-1 17.04 15.73 25.30 8.3% 0.62P-5-4-2 14.58 13.40 21.63 8.8% 0.62P-5-4-3 18.19 16.80 26.08 8.3% 0.64P-5-4-4 16.65 15.33 26.66 8.6% 0.58P-5-4-5 19.19 17.70 26.10 8.4% 0.68P-5-4-6 15.66 14.34 22.50 9.2% 0.64P-5-7-1 15.40 14.13 23.69 9.0% 0.60P-5-7-2 15.56 14.22 22.70 9.4% 0.63P-5-7-3 16.70 15.41 25.64 8.4% 0.60P-5-7-4 15.02 13.90 23.58 8.1% 0.59P-5-7-5 17.66 16.15 26.23 9.3% 0.62P-5-7-6 16.45 15.17 25.24 8.4% 0.60

P-5-10-1 19.07 17.58 25.60 8.5% 0.69P-5-10-2 18.53 17.07 26.16 8.6% 0.65P-5-10-3 17.91 16.45 27.10 8.9% 0.61P-5-10-4 17.74 16.28 24.83 9.0% 0.66P-5-10-5 19.17 17.66 26.10 8.6% 0.68P-5-10-6 16.61 15.27 25.18 8.8% 0.61P-3-4-1 14.69 13.45 23.64 9.2% 0.57P-3-4-2 15.44 14.21 23.43 8.7% 0.61P-3-4-3 16.29 14.98 24.26 8.7% 0.62P-3-4-4 15.92 14.63 24.02 8.8% 0.61P-3-4-5 17.37 15.94 25.40 9.0% 0.63P-3-4-6 16.46 15.11 23.76 8.9% 0.64P-0-4-1 17.78 16.36 24.50 8.7% 0.67P-0-4-2 17.87 16.43 26.56 8.8% 0.62P-0-4-3 15.69 14.34 24.02 9.4% 0.60P-0-7-1 17.79 16.24 25.30 9.5% 0.64P-0-7-2 19.79 18.16 27.43 9.0% 0.66P-0-7-3 18.12 16.63 27.08 9.0% 0.61Mean 16.81 15.44 24.60 8.9% 0.63St Dev 1.46 1.36 1.65 0.5% 0.03

COV (%) 8.7% 8.8% 6.7% 5.1% 4.5%

Moisture Content and Specific Gravity Results: PSL

Vita 181

Vita David Edward Finkenbinder was born in Chambersburg, Pennsylvania on April

23, 1981 to Dewaine and Theresa Finkenbinder. He grew up in Shippensburg,

Pennsylvania. Following his high school graduation from Shippensburg High School in

1999, David attended Shippensburg University in his hometown, and The Pennsylvania

State University in University Park, Pennsylvania. He graduated in 2004 with a

Bachelors of Science degree in Agricultural & Biological Engineering, and in 2005 with

a Bachelors of Science degree in Applied Physics. David then pursued a Masters of

Science degree in Structural Engineering at Virginia Tech. Upon completion of his

graduate degree, David will begin a career in structural design.

an experimental investigation of structural composite lumber … · 2020-01-20 · lumber (lvl),...

Documents