Download - Keystone

DESIGN MANUAL& KEYWALL OPERATING GUIDEBNCMA 2ND EDITION - COULOMB METHODOLOGY LEVEL SURCHARGE - 250 PSF6) OverturningOverturning MomentM o = P ah (H ⁄ 3) + P qh (H ⁄ 2)= 1543 lbs (10' ⁄ 3) + 643 lbs (10' ⁄ 2)= 8358 ft-lbsResisting MomentM r = W f x W u ⁄ 2 + W 1 x (W u + L ⁄ 2)= (2100 x 1.75' ⁄ 2) + 8700(1.75' + 7.25' ⁄ 2)= 48600 ft-lbsFS ot = M r /M o = 48600/8358 = 5.81> 1.5 OK7) Base SlidingLateral Driving ForcesR d = P ah + P qh= 1543 lbs + 643 lbs= 2186 lbs/ftLateral Resisting ForcesR r = (W f + W 1 ) x Tan φ of foundation= (2148 + 8652 ) x Tan 30= 6235 lbs/ftFS sl = R r ⁄ R d = 6235/2186 = 2.85> 1.5 OK8) Sliding at Lowest Reinforcement LevelLateral Driving Forces (at depth of 9.33')R d = P ah + P qh= 1344 lbs + 600 lbs= 1944 lbs/ftLateral Resisting Forces (at depth of 9.33')τ unit = 1550 + N x Tan 17.4= 1550 plf + (9.33' x 1.75' x 120 pcf) Tan 17.4= 2164 plfτ soil = (γ H (B-W u ) x Tan φ (of reinforced material) x C ds= 120 pcf x 9.33' x 7.25' x Tan 34 x 0.90= 4928 lbs/ftFS sl = R r ⁄ R d = (2164+4928)/1944 = 3.65> 1.5 OKB.3