1. Final Presentation for CE 331 Introduction to Structural Engineering

2. Your Assignment for Project 2 was to: Visit a construction site Photograph structural components, copy structural drawings Calculate structural adequacy

3. Describes your structure Summarizes your structural analysis Create an interesting presentation that: PuPu PnPn

4. The following slides are examples. Feel free to use copy and paste any sketches into your own presentation.

5. Gravity Load Analysis for Sears Tower for CE 331, Spring 2007 Project 2 by Matt Damon and Jennifer Lopez

6. The Sears Tower is a 108-story steel-frame office building in downtown Chicago Illinois. ( Original) Owner: Sears & Roebuck Co. Contractor: Morse-Diesel Inc. Structural Engineer: Skidmore, Owings, and Merrill

7. The Sears Tower is constructed of nine steel “tubes”, each 75 feet across.

8. Insert several slides using your own photos here.

9. We analyzed a typical interior column and spread footing. Elevation View - steel tube column - reinforced concrete foundation - steel roof deck - bar joist - joist girder

10. Roof dead load = 14 psf waterproof membrane4 psf steel deck4 psf purlins3 psf suspended ceiling2 psf sprinklers1 psf 14 psf Section of Roof

11. We checked the design of an interior column for axial buckling. PuPu  P n

12. Column live load = 15 psf Specified live load = 20 psf Interior Column

13. Column live load = 15 psf specified live load = 20 psf tributary area = 525 sf live load reduction factor = 0.75 reduced live load = 15 psf

14. Factored load to column (P u ) = 30.6 k Pu = [ 1.2 (14psf) + 1.6 (15psf) ] (30ft)(25ft) = 30.6k PuPu

15. Column capacity (P n ) = 44 k failure mode: axial buckling grade 50 steelE = 29,000 ksi fy = 50ksi slenderness (kL u /r)r = 23.4 in k = 1.0 Lu = 10.5 ft AISC TablePn = 44 k HSS 3x4x3/16

16. Design check shows column design is OK PuPu  P n

17. We checked the design of a typical reinforced concrete spread footing for flexure failure.

18. Flexure failure occurs when demand (Mu) exceeds capacity (  Mn). location of flexure failure factored soil pressure, q u P u, factored axial force from column ququ C T Mn Mu