1. Computer Associates International, Regional Office
Herndon, VA
Seth R. Takoch
AE Senior Thesis
Structural Option
April 15, 2003

2. Presentation Outline Background Information
Existing Structural Conditions
Design Criteria
Redesign
Construction Management
Lighting Design
Conclusions and Recommendation
Acknowledgements
SETH R. TAKOCH STRUCTURAL OPTION

3. Location 15min. Off Beltway 35mins. Outside D.C Wood Oak Dr.
Baseball Field

4. Background Information
Function: Computer Associates Int. Regional Headquarters
Size: 233,000 sq. ft. – 6 floors
Rentable Office Space: 207,000 sq. ft.
Architectural Features:
Precast Concrete Façade with Glass Curtain Wall
Six Story Glass Enclosed Atrium
Adjacent Day Care Facility

5. Project Team Owner – Computer Associates International
Arcitect – Davis, Carter, Scott
Structural Engineer – Smislova, Kehnemui, & Associates.
General Contractor – Clark Construction
Developer – Tishman Speyer Properties
Mechanical – GHT Limited
Plumbing – GHT Limited

6. Existing Structure Flat Slab Construction Concrete Structure
30’ x 30’ Bays
9” Thick Slab Thickness
10’ x 10’ x 5-1/2” Drop Panels
24” x 24” Conc. Columns

7. Existing Structure
Wind Loads are Transferred by Diaphragm Action of Façade
Transferred to Framing by Tributary Area
8 Frames N-S and 9 Frames E-W
Concrete Frames Resist Lateral Forces
Short and Long Frames
Floor Slab Adds Resistance due to Diaphragm Action

8. Design Limitations 50 psf 22 psf 30 psf Old Code – BOCA 96
New Code – IBC 2000
Local Zoning Ordinances
Similar Square Footage
Minimal Architectural Changes
Floor-to-Floor Heights
LIVE LOADS PER IBC 2000
LOAD TYPE
LOAD
ROOF ( RAIN )
50 psf
ROOF ( SNOW ) HIGH ROOF
22 psf
ROOF (SNOW) LOW ROOF
30 psf
OFFICES, CUBICLES
ASSEMBLY, STAIRS
100 psf
MECHANICAL
150 psf
CORRIDORS
80 psf

9. Proposal
To Redesign a Feasible and Desirable Alternative Structural System and to Incorporate Construction Costs and Schedule Length Into My Solution
Time = Money …
Money = Time
$$$$

10. Possible Faming Alternatives
Composite Steel Construction
Non-Composite Steel Construction

11. Steel Construction Code – IBC2000 LRFD Analysis Parameters
30’ x30’ Typical Bays
Fy = 50ksi ASTM A992 Steel
F’c = 3ksi
Normal Weight Concrete
Shear Studs - 3-1/2”high, ¾” diameter (composite)
22 gage Metal Deck

12. Composite Steel Construction
Gravity Analysis – RAM
Determined Beam Sizes
Determined Column Sizes
2 Story Column Lengths 26’ – 28’ Tall
Ranging from W10’s to W12’s
Beam Sizes W12x14 Spaced at 6’ o.c.
Girders as Deep as a W21’s

13. Non-Composite Construction
Gravity Analysis – RAM
Determined Beam Sizes
Determined Column Sizes
2 Story Column Lengths 26’ – 28’ Tall
Using W12’s
Beam Sizes W12x14 Spaced at 6’ o.c.
Girders as Deep as a W24’s

14. Depth Comparison Composite Steel Average – W12’s Critical Depth – W21
Composite Saves 20 Tons
of Steel
Non-Composite Steel
Average – W12’s
Critical Depth – W24
Advantage – Composite Steel Construction

15. Lateral System Shear Wall to Resist Lateral Loading
Based on Critical Wind Loading and Torsion
2 – 60’ Long Shear Walls
Reinforced to Resist Forces
Deflection of h/400

16. Design Reinforcement Based on the Following
Wall
Floor
Shear
Bending 1
12"
8 - #11 2
6 - #11 3
6 - #9 4
12"
4 - #9 5
12"
2 - #9 6
12"
1 - #9
12"
12"
12"
Reinforcement Based on the Following
Vn =  (2f’c bd + Avfyvd/s)
Mn = Asfy (d-a/2)

17. Construction Management`
Address Two Main Issues
Cost Comparison
Project Duration

18. Construction Management`
Total Building Cost
D4 Cost
Total = $27,678,667
20-25% Accurate
Range of $34.6 million to $20.8 million
Not Very Accurate
$ / sq. ft.

19. Construction Management`
Total Building Cost
Means Building Construction Cost Data
Separate Estimates for Steel and Concrete
10 -15% Accurate
More Precise Than D4
Steel Framing = $96.74 / sq.ft.
Concrete Frame = $98.45 / sq.ft.
Difference = $1.71 / sq.ft. = $410,400

20. Construction Management`
Cost Comparison
D4 Cost = $115.33/sq.ft. = $27,678,667
Means Steel = $96.74/sq.ft. = $23,217,600
Means Concrete = $98.45/sq.ft. = $23,628,000
Percentage Savings Using Steel = 1.7% Savings

21. Construction Management`
Scheduling
Means Data to Calculate Duration
Primavera Utilized to Schedule Sequences
Total Duration Steel Erection = 376days
Total Duration Concrete Placement = 847 days

22. Construction Management`
After Scheduling Concrete – 260 Days

23. Construction Management`
After Scheduling – 150 Days

24. Construction Management`
Savings
Advantage Composite Steel Construction
Time
Advantage Composite Steel Construction
Composite Design is Considered One of the Most Economical Methods of Floor Construction for an Office Building

25. Construction Management`
Crane Sizing
On Site 3-1/2 Months
Tower Crane
Placed Through Atrium
Liebherr 200HC
Hook Radius – 197ft.
Capacity – 5,070#
Satisfies Critical Lift of

26. Lighting Design Design of Lighting of Daycare Facility
Minimum Footcandles of 30fc
Fluorescent Luminaries
120’ x 56’ Space to Illuminate
2’ x 4’ Fixtures with 3” Louvers Spaced on a 16’ x 8’ grid
Specification From Lithonia
Workplane of 2-1/2 ft.

27. Lighting Design Designed Using Luxicon Renderings on April 15, 2003
At 9:00 am with Daylighting
At 1:30 pm with Daylighting
At 5:00 pm with Daylighting
Without Daylighting

28. Lighting Design
9:00 am

29. Lighting Design
At 1:30 pm

30. Lighting Design
At 5:00 pm

31. Lighting Design
Without Daylighting

32. Lighting Design
The Lighting Design Meets Required Parameters of 30fc

33. Conclusion
In Conclusion, Composite Steel Construction is a Better Alternative to Non-Composite Construction.
Composite Steel is a Viable Alternative to a Two-Way Flat Slab System

34. Shout Outs’ My Family My Friends The AE Student Body
The Entire AE Faculity
Smislova, Kehnemui, & Associates, P.A.
Computer Associates
The ‘U’
And All Of Those Out There That Stuck With Me

35. ?
Questions