urs – arena district office building david lee structural option

URS – ARENA DISTRICT OFFICE BUILDING

DAVID LEE

STRUCTURAL OPTION

PRESENTATION OUTLINE

1. EXISTING CONDITIONS

2. DEPTH STUDY

3. BREADTH STUDY

4. CONCLUSION & RECOMMENDATION

David LeeStructural OptionURS – Arena District Office Building

EXISTING CONDITIONS 1

• Located in Columbus, Ohio

• 5 story – 100,000 SF building

• March 2000 – January 2001

construction duration

• Total project cost $7 million

David LeeStructural OptionURS – Arena District Office Building Building Statistics



OHIO BASIC BUILDING CODE 1998

STRUCTURAL STEEL

AISC Manual of Steel Construction

CAST IN PLACE

CONCRETE

ACI 318 – “Building Code Requirement for Reinforced Concrete”ACI 301-89 – “Specification for Structural Concrete for Buildings”

PRECAST CONCRETE

ACI 318 – “Building Code Requirement for Reinforced Concrete”PCI MNL 120 – “PCI Design Handbook Pre-cast and Pre-stressed Concrete”

METAL DECK

AISI – “Specification for the Design of Cold-formed Steel Structural Members”SDI – “Design Manual for Composite Decks, Form Deck, and Roof Decks”

MASONRY ACI 530.1/ASCE 6/TMS 602 Table 1

Building Code


David LeeStructural OptionURS – Arena District Office Building Typical Floor Framing



Lateral Load Direction

Factored Base Shear

Due to WIND

Factored Base Shear

Due to SEISMIC

North-South Loading

Considered Y281.38 kip 169.30 kips

East-West Loading Considered X

142.8 kips 169.30 kips

Existing Lateral System

Y

X



Center of Mass

Center of Rigidity

FloorHeight (feet)

Floor to Floor

Height

Max Displacement

X (inch) Y (inch)

R 72 14 1.456 1.019

5 58 14 1.232 0.855

4 44 14 0.957 0.67

3 30 14 0.641 0.438

2 16 16 0.304 0.209

Story Drift

Seismic Story Drift LimitX (inch) Y (inch)

0.672 0.164 3.36

0.825 0.185 3.36

0.948 0.232 3.36

1.011 0.229 3.36

0.912 0.209 3.84

Drift and Torsion



2. DEPTH STUDY

3. BREADTH STUDY



DEPTH STUDY 1

OBJECTIVES

• Eliminate Moment Frames• Reduce Floor Depth


CONSTRAINTS

• North and West façade must be free of obstruction• Large open floor space must be maintained

Objectives and Constraints

Design:• Removed both moment frames • Added a braced frame

Result:• Reduced eccentricity

David LeeStructural OptionURS – Arena District Office Building Steel Alternative

DEPTH STUDY 2

Steel Member Size

New steel frame identical to braced frame 1


DEPTH STUDY 3

Steel Alternative


DEPTH STUDY 4

Steel Alternative

Constraint Met & Design Goal Achieved


DEPTH STUDY 5

Steel Alternative

Drift and Story Drift

Calculated Maximum Drift L/780

*due to wind

X (inch) Y (inch) X (inch) Y (inch)R 72 14 1.004 1.101 2.16 0.519 0.184 0.425 58 14 0.831 0.917 1.74 0.687 0.201 0.424 44 14 0.602 0.716 1.32 0.657 0.251 0.423 30 14 0.383 0.465 0.9 0.645 0.243 0.422 16 16 0.168 0.222 0.48 0.504 0.222 0.48

H/400 Drift

Story Drift H/400 Story DriftFloor

Height (feet)

Floor to Floor

HeightMax Displacement


DEPTH STUDY 6

Concrete Alternative

Concrete Design

•Flat plate 2 way PT slab

•CIP columns

•Shearwalls


DEPTH STUDY 7


Recalculate Loads•Self weight of building increase from 52 PSF to 106 PSF

•Seismic lateral load controls in both X and Y direction LOAD TYPE

Factored Load In X direction

Factored Load In Y direction

WIND 143 kip 281 kipSEISMIC 323 kip 323 kip

8.5” concrete slab with density of

150PCF = 106PSF


DEPTH STUDY 8


PT Slab Design

•Feasibility domain created to obtain possible force, eccentricity combination•Steel envelop developed after tendon force is determined

Y

X


DEPTH STUDY 9


Max initial deflection = 0.1”

Max sustained deflection = 0.46”

Max long term deflection = 1.58”

Limit Floor Deflection

L = l/360D+L = l/240


DEPTH STUDY 10


CIP Column•Perform gravity design•Consider slenderness effects•Check punching shear

Interaction Diagram

0

500

1000

1500

2000

2500

0 100 200 300 400 500 600 700

Moment (ft-k)

Fo

rce

(k)


DEPTH STUDY 11


Shearwalls•Coincide with elevator shaft and stairwell•Max Drift = l/1000

Foundation•Larger footings needed•Existing foundations require 350CY of concrete•Concrete design require 1000CY of concrete for foundation



2. DEPTH STUDY

3. BREADTH STUDY




BREADTH STUDY 1

Cost and Schedule

Considerations•Cost

•Construction Duration

•Constructability

RS MEANS Steel Concrete

Cost ($/SF) 15.58 16.80

Duration (days) 27 53



2. DEPTH STUDY

3. BREADTH STUDY




CONCLUSION & RECOMMENDATION

Recommendation

Steel•Construction cost savings of $122,000•Shorter construction duration•Majority of office building in Columbus use steel frame

Concrete•Cost savings due to reduced floor depth•Flexibility in on-site alterations•No lead time

ACKNOWLEDGEMENTSURS Corporation

Bill Huckleberry, Structural Engineer

ONCORE ConstructionRaymond E. Sowers

AE FacultyProfessor Andres Lepage

Professor M. Kevin Parfitt Professor Jelena SrebricProfessor John MessnerRest of the AE Faculty

AE StudentsSean Flynn

Brian Ault

ANDAll my family and friendsDavid Lee

Structural OptionURS – Arena District Office Building

QUESTIONS ?

urs – arena district office building david lee structural option

Documents

steel alternativedrift

existing conditions2

kipsexisting conditions

building code requirement

depth study3

breadth study4

design of cold

sf building