2001 ASD Supplements - unprotected PDF - American Wood Council

SW-36APPENDICESStep 9.Hold-down Design for East and West WallsLOAD ON WALLS:Total Diaphragm Load to beResisted by Lateral SystemDistributed Lateral LoadAlong East and West WallsV seismic = 53,768 lb. ÷ 2 = 26,884 lb.V wind = 61,519 lb. ÷ 2 = 30,760 lb.LATERAL LOADS:East wall (70 ft.)West wall (45 ft.)SeismicWindSeismicWind==At RoofLevel26,884 lb.30,760 lb.26,884 lb.30,760 lb.Contribution FromWall WeightAt Mid-Story Level0.2 x (8 psf x 70'x26') = 2,912 lb.0.2 x (8 psf x 45'x26') = 1,872 lb.OVERTURNING MOMENTS:East wall (70 ft.)West wall (45 ft.)SeismicWindSeismicWindDue to DistributedLateral Loads26,884 lb. x 24'30,760 lb. x 24'26,884 lb. x 24'30,760 lb. x 24'Due toSelf-WeightTotalOverturning+ 2,912 lb. x 13' = 683,072 ft-lb.738,240 ft-lb.+ 1,872 lb. x 13' = 669,552 ft-lb.738,840 ft-lb.RESISTING LOADS:East wall Roof(70 ft.) WallHeaderWest wall(45 ft.)RoofWallHeader10 psf x 15'8 psf x 26'10 psf x 15'10 psf x 15'8 psf x 26'10 psf x 15'==x==x150 lb./ft.208 lb./ft.40'150 lb./ft.208 lb./ft.20'x 70' =x 70' =÷ 2 =x 45' =x 45' =÷ 2 =10,500 lb.14,560 lb.3,000 lb.6,750 lb.9,360 lb.1,500 lb.at centerat centerat int. wall endat centerat centerat int. wall endRESISTING MOMENTS:East wall (70 ft.) w/o headerheaderWest wall (45 ft.) w/o headerheader(10,500 lb. + 14,560 lb.) x 35'3,000 lb. x 70'(6,750 lb. + 9,360 lb.) x 22.5'1,500 lb. x 45'= 877,100 ft.-lb.210,000 ft.-lb.= 362, 475 ft.-lb.67,500 ft.-lb.NET UPLIFT AT THE ENDS OF SHEAR WALLS AND HOLD-DOWN REQUIREMENTS:Gross Overturning(ft.-lb.)ReductionFactorDLGrossResisting(ft.-lb.)DesignResisting(ft.-lb.) (lb.)East wall(70 ft.)West wall(45 ft.)SeismicWindSeismicWindinteriorcornerinteriorcornerinteriorcornerinteriorcorner683,072683,072738,240738,240669,552669,552738,240738,2400.85 x0.85 x2/3 x2/3 x0.85 x0.85 x2/3 x2/3 x1,087,100877,1001,087,100877,100429,975362,475429,975362,475= 924,035= 745,535= 724,733= 584,733= 369,479= 308,104= 286,650= 241,650Net ResistingN/A ÷ 70'N/A ÷ 70'13,507 ÷ 70'153,507 ÷ 70'300,073 ÷ 45'361,448 ÷ 45'451,590 ÷ 45'496,590 ÷ 45'NetUplift(lb.)N/AN/A1932,1936,6688,03210,03511,035APA – The Engineered Wood Association