Question

Question-5 (20%): If a rectangular foundation of a dimension 1 X 1m with a load equal to 200 kN is placed at Im below the ground level as shown in the figure below. Calculate the maximum elastic settlement and settlement caused by primary consolidation due to the imposed load knowing that the clay is normally consolidated clay Ground level Es (kN/m2) 10000 Yd = 15 kN/m3 3m 5m Sand B000 Hs =0.3 2m Cc = 0.3 Ysat = 20 kN/m Clay 3m eo = 0.8

Answer 1

P = 200KN 3m didn N2 = 15 kN/m² SCO. 3 Brim che 27 G.H.LV Cc = 0.3 / 1 Gat = 20 kN) mp 11:59 #=377 w X e, 20-3 im 2.75m 115m Elastic Settlement !t Elestic desormation of soil is denoted by 98 Cine x It Es S = 200 2 Ini oq = pressure at the base of foundation = 200 XN/m Mo= 0.3 (Giren) Ita influence / Shope fachar = 1 (for square footing Eg = young's modules of soil (3-1) + 8000x2 I weightagen 10010 mean process Es effective. (3-0) + 2 [N.B N.B We deduct I'm from 3m ho because soil above the booting dees not affect the elastic selblement so Effective depth for first layer am - 1m2 am am] Es = 4000 kN/m? of

XI 200* 1 *(1-0.33)* .. S = 9000 =/20.22 mm = 0.0202 m ④ Maximum elastic selblement = 20.22 mm layer » pressure distribution of applica load by 2:1 So. Effective width, B at the mid section of clay 3+2+15)-1 B + 2x L because of two side хь х! z 2 E B 6.5 ms R = 1 t 3+ 2otas - 1 at x-X section Effective overberden pressure 1.5 90.285 kN/m2 T = (5x 15) + (20-19,81) ** Lovw=9.84 kilos ra rsat 200 KN load, increased stress due to 200 200 = 4.733 km/com 2 s5= 6.52 (CO2 H = 3m 6 20.8 les 03 Consolidation Settlement caused by primary us given by

czu Hee teo Д» (о go ta5 . 90-285+ 4.733 90.285 3 X 0.3 18 - 1+0.8 = 0.0110 g 5 m = 11:095 mm settlement caused by primary Consalidation 11-095 mm