1. OVERLOOK TOWERS AT DULLES CORNER HERNDON, VIRGINIA Anthony Perrotta AE Senior Thesis – Structural Option

2. Outline

3. Primary Project Team Owner: S. Vardell Realty Investments, L.L.C. Architect: Noritake Associates Landscape Architect: Lewis Scully Gionet Structural Engineer: Haynes Whaley Associates M.E.P. : KTA Group Inc. Civil Engineer: William H. Gordon Associates CM: Clark Construction

4. Overlook Towers at Dulles Corner Herndon, VA Building Overview & Existing Conditions

5. Building Location Overlook Towers at Dulles Corner 2550 Waser Terrace Herndon, Virginia

6. Building Summary  3 Building Complex  Sept. 2006 – December 2007  $ 20.5 million 262,000 s.f. 190,000 s.f. Project Timeframe:

7. Building Design 219’ x 125’ 24,000 s.f. per floor 13’-6” typical floor height

8. Building Design 219’-2” 219’ x 125’ 24,000 s.f. per floor 13’-6” typical floor height

9. Building Design 219’-2” 125’ 219’ x 125’ 24,000 s.f. per floor 13’-6” typical floor height

10. Building Design

11. 21,000 s.f. of Office Space

12. Existing Floor System Foundation : Elevated Slab: Spread footings & Grade Beams 4” thick 4,000 psi SOG 10 mil vapor barrier 4” compacted granular stone

13. Framing Plan

14. Typical Bay Exterior: 30’-0” x 46’-0” Interior: 30’-0” x 30’-0” W24x55 (typical beam size) Controlling Size: 30’-0” x 46’-0” Exterior Bay 12’-6” o.c. Beam Spacing Design Loads (IBC 2000): Office Space: 100 psf Corridors: 100 psf Mechanical: 125 psf Dead: 25 psf superimposed Controlling Size: 30’-0” x 46’-0” Exterior Bay 12’-6” o.c. Beam Spacing Design Loads (IBC 2000): Office Space: 100 psf Corridors: 100 psf Mechanical: 125 psf Dead: 25 psf superimposed

15. Lateral System 4 Steel Braced Frames Located around Central Core

16. Design Loads Gravity LoadsLive Loads Mechanical & Ceiling5 PSF Roof Snow Load30 PSF Single Ply Roof11 PSF Office Space100 PSF FinishesAs RequiredPermanent Corridors100 PSF Sprinkler SystemAs RequiredLobbies & Stairs100 PSF Mechanical Space*125 PSF IBC 2000: ASCE7-05: Wind LoadingSeismic Loading Wind Speed90 mphSeismic Use GroupI Importance Factor1.0Importance Factor1.0 Wind ExposureBDesign CategoryB Enclosure Class.0.18

17. Design Loads Wind Loading (N-S):Seismic (N-S):

18. Depth Analysis Alternate Structural System

19. Design Goals

20. Proposed Floor System Precast Double-T Slab 15LDT26 Typical span of 46 feet. Designed to carry a load of 120 psf. Dead Load: 57 psf. < 126 psf 19% Lighter

21. Proposed Floor System Precast IT & L-BEAM 30’ & 46’ Exterior Spans 30’ Interior Spans Dead Load: 800 plf 6.7 klf < 7.1 klf Dead Load: 625 plf 4.1 klf < 5.2 klf Much heavier than W-shapes.

22. Precast Framing Plan

23. Lateral System

24. 1 2 3 4 Does not disturb architectural design of building. Cheap and efficient design. No downtime from concrete curing.

25. Lateral System highlighted Structural Model

26. Breadth Analysis Construction Management

27. Project Schedule  Common Start:  10/02/07  Avg. Floor Completion:  26 days  End Structural Construction  3/22/07  10/02/07  16 days  3/14/07 ExistingProposed 6 Days Earlier

28. Project Schedule Existing: Proposed:

29. Project Estimate  Key Costs  Elev. Slab: $ 1.01million  Steel: $ 2.4 million  Fireproofing: $182,000  Overall Structural Cost  $4 million  Key Costs  Double-T: $1.4 million  Beams: $1.2 million  Fireproofing: $65,000  $3.6 million ExistingProposed Possible Savings of $ 400,000

30. Summary  Building Weight:  Construction Schedule:  Building Cost:  ~ 4.1 % Lighter  Less 6 days  Possible 10% Savings ExistingProposed

31. Summary  Building Weight:  Construction Schedule:  Building Cost:  ~ 4.1 % Lighter  Less 6 days  Possible 10% Savings ExistingProposed