1 bcsi 06 for information on: jobsite storage truss handling temporary bracing fall protection ...

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BCSI 06

For information on: Jobsite storage Truss handling Temporary bracing Fall protection Construction loading

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ContentsB1 – Handling, Installation and

BracingB2 – Installation and BracingB3 – Web Bracing/ReinforcementB4 – Construction LoadingB5 – Damage, Modifications and ErrorsB6 – Gable End Frame BracingB7 – Parallel Chord TrussesB8 – Toe-nailing for UpliftB9 – Multi-Ply TrussesB10 – Post Frame TrussesB11 – Fall Protection

Development of BCSI

Engineers Manufacturers

Manufacturers Suppliers Contractors

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BCSI Booklet Replaces…

HIB-91 Booklet

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BCSI B-Series

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BCSI B-Series Replaces...

HIB-91 Sheet

HIB-98 Poster

WTCA-B1 Warning Poster TTB WTCA-B2

B1 Guide for Handling,Installing & Bracing

Consequences of improper installation may be collapse of the structure

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B1 Summary Sheet

HIB-91 Sheet

WTCA-B1 Warning Poster

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B1 Banding Warning

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B1 Handling

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B1 Handling

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B1 Storage

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B1 Storage

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B1 Hand Erection

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B1 Hoisting

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B1 Hoisting Recommendations

From BCSI Booklet

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From BCSI Booklet

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From BCSI Booklet

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B1 Bracing Warning

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B1 Ground Bracing

B1 Top Chord BracingSee

TCTLBTable

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B1 Bottom Chord Bracing

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B1 Web Plane Bracing

Lateral brace splicing

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Look for “Truss Brace Splicing Methods” in the November SBC Magazine

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B1 PCT Bracing

(PCT)(PCT)

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B1 Diagonal Bracing

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B1 Truss Installation

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B1 Constructions Loads

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B1 Construction Loads

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B1 Alterations

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B2 Truss Installation & Temporary Bracing

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B2 Scope

From p.8:

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B2 Scope

B2 Doesn’t Cover These3x2 or 4x2 Flat Trusses Trusses spaced > 2 ft. o.c.

From p. 8 From p. 8

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B2 Warnings

B2 Top Chord Bracing

Ground bracing not shown Take special care with spans over 60 ft.

B2 Checklist

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B2 Steps to Setting Trusses

B2 Step 2 - Ground Braces

B2 Step 3 - Set First Truss

B2 Step 4 - Next 4 Trusses

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B2 Step 4 - TCTLB Options

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B2 Note on Bracing Materials

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B2 Step 5 - Top Chord Diagonals

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B2 Step 5 - Top Chord Sheathing

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B2 Step 6 – Web Bracing

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B2 Step 6 – High End Trusses

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B2 Step 7 – Bottom Chord Bracing

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B2 Step 8 – Repeat Groups of 4

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B2 Sheath Early and Often

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B2 Alternate Installation Method

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B2 Special Conditions

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B3 Web Member Permanent Bracing/Web Reinforcement

B3 Compression Web Members

Unstable if unrestrained Check Design Drawing if restraint

req’d

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B3 Bracing vs. Reinforcement

Bracing provides lateral support, reducing buckling length

Reinforcement increases cross-section, making web more stable

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B3 Six Methods of Restraint

These items apply to all six methods:

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B3 CLBs and Diagonals

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B3 T-Reinforcement

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B3 L-Reinforcement

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B3 Scab Reinforcement

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B3 Metal Reinforcement

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B3 Stacked Webs

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B3 Gable End Frame Bracing

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B3 Gable End Frames Designed to

transfer vertical loads

But may also experience lateral loads Sheathing,

bracing and connections must be designed for this transfer

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B3 Load Transfer Path

B3 Poorly Designed System

B3 Design Considerations Gable End Frame

Reinforcement prevents failure of individual vertical webs

Frame to End Wall

Correct connection prevents hinge joint

Bracing, blocking and diaphragm design creates safe load path

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B3 Bracing and Blocking

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B3 Bracing and Blocking

B3 Gable End Reinforcement

Horizontal reinforcement:

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Individual L- or T-reinforcements


Scab reinforcements

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B3 Building Designer Detail

B3 Building Designer Detail

B3 Avoid Hinge Joint

Balloon Framed End Wall

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B3 Scissor Truss End Wall

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B3 Avoid hinge points in walls!

Additional Note: This wall will not meet the prescriptive method criteria under IRC for a braced wall.

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B4 Construction Loading

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B4 Construction Loads

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B4 Loading DOs and DON’Ts

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B5 Truss Damage, Modifications and Installation

Errors

B5 Truss Damages

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B5 Steps for Repair

B5 Repair Techniques

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B5 Report Damage

B5 Truss Repair Detail

B6 Section

B6 used to be on Gable end bracing that information has now moved to section B3.

B6 is intended to be used for additional topics in future additions of BCSI

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B7 Parallel Chord Trusses

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B7 Lumber Orientation

Guidelines for 3x2 or 4x2 only

For 2x_ orientationsee BCSI-B2

B7 PCT Bearing

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B7 Temporary Bracing

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B7 Stabilize Truss Ends Temporary Bracing or Permanent Blocking

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B7 Correct Placement

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B7 Truss Tags

B7 Strongback Bridging Helps limit deflection and/or

vibration

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B7 Construction Loads on PCT

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B8 Toe-Nailing for Uplift

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B8 Uplift Forces

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B8 Toe-Nailed Connections Are three toe-nails enough?

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B8 1- Proper Toenail Installation

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B8 2- Top Plate Lumber Grade and

species

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B8 3- Type of Nails

0.162″ x 3.5″

B8 Is Toe-Nailing Enough? Toe-nail values must exceed expected uplift

For example:A 16d common ina Southern Pinetop plate offers72 pounds ofuplift resistance.

If there are threetoe-nails, the totaluplift resistanceIs 3x72=216 pounds

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B8 Load Duration Factors

For wind uplift resistance use the factor of 1.6.Therefore, 216x1.6 = 346 pounds

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B8 Alternatives to Toe-Nailing

Check published uplift capacities of mechanical connectors

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R802.10.5 Truss to wall connection

Trusses shall be connected to wall plates by the use of approved connectors having a resistance to uplift of not less than 175 pounds (79.45 kg.) and shall be installed in accordance with the manufacturer's specifications. For roof assemblies subject to wind uplift pressures of 20 pounds per square foot (0.958 kN/m2) or greater, as established in Table R301.2(2), adjusted for height and exposure per Table R301.2(3), see section R802.11.

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IRC R802.10.5 The code requirement was added in the IRC

2003 in a perhaps well-intentioned effort to address a perceived issue from the proponent's point of view. Now that it is in the code, it is proving difficult to

remove. A number of code jurisdictions have amended the language

or struck the language out of their code adoption. The 175 lb value is unrelated to any real design parameters

or linked to any truss length. It arbitrarily discriminates against one well respected construction method. No specific evidence was or can be provided to justify this requirement.

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IRC R802.10.5 TPI 1 requires that a Truss Design

Drawing include reaction forces and directions, which would include a value for uplift based upon the structure's design parameters for wind. There is no valid reason for not using this

calculated value in the consideration of the uplift connection requirements.

IRC R802.10.5 Much of the US is in the 90 mph basic wind speed

zone. The resistance for uplift, beyond the prescriptive fastening

requirements of Table R602.3(1) is really seldom an issue, especially for structures categorized as Exposure B and with a Mean Roof Height of less than 30 feet. IRC Table R301.2(2) is used to trigger the need for special

connection requirements per Table R802.11. Only high wind speed areas, highly exposed structures or extremely tall structures ever qualify for the special requirements. When the calculated uplift requires a connection of a specific value, WTCA supports providing resistance in a manner acceptable to the EOR or building code official, not based upon an arbitrary requirement.

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B9 Multi-ply Girders

B9 Girders Designed to carry extra loads Max. 6 plies, fastened together to act as one

4-ply 5-ply

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B9 Fastener Schedule Specified on

Truss Design Drawing

SAMPLE

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B9 Nail Fasteners Fasteners using nails only are

specified on girders with three plies or less

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B9 Screw Fasteners Special screws on up to four plies

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B9 Screw Fasteners Screws on 2-ply 3x or 4x2 floor-type

trusses

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B9 Bolt Fasteners Bolts on 4 to 6 plies In addition, nails may also be required

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B9 Good Installation Practices

Fasten plies together before lifting, if possible

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B10 Post Frame Trusses

HIB-98 Poster

B10 Post Frame Trusses Part of an engineered building system Spaced at 4′ to 12′ o.c. Heels attached to posts fixed in ground or

slab Purlins attached directly to truss top chords

B10 Truss Storage

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B10 Installation

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B10 Installation

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B10 1- Ensure Stable Columns

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B10 2- Stable Base Unit

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B10 3- Bracing of Base Unit Top Chord

A professional engineer should design a bracing plan for truss spans over 60’ per BCSI Fig.B2-13

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B10 3- Bracing of Base Unit Bottom Chord

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B10 3- Bracing of Base Unit In the Roof Plane

- or -

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B10 3- Bracing of Base Unit In the Web Plane

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B11 Fall Protection & Trusses

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B11 Fall Protection Warning

Trusses alone are notdesigned to supportfall protection anchors

B11 Impact Loads A falling worker could cause the

trusses to collapse in a domino effect

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B11 Safer Options

Option 1: Scaffolding

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B11 Safer Options

Option 1: Roof Peak Anchor

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B11 Safer Options

Option 1: Ground Assembly

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Jobsite Safety Package B1 through B4 Handling Checklist

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Truss Tags

145Questions on BCSI?Questions on BCSI?

1 bcsi 06 for information on: jobsite storage truss handling temporary bracing fall protection ...

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