Question

2. Vane shear strength. c, (field) (tre) A continuous foundation is shown in the attached figure, along with the field vane shear test results. Estimate the gross allowable bearing capacity for FS = 3 and y = 121 lb/ft" Solve the problem in two ways: a) Calculate the weighted shear strength within the relevant depth and use the general B.C. equation. b) Treating the subsurface as a two- layer system (refer to Section 4.3). Depth (ft)

Answer 1

Given data, FS = 3 1 22 121 lbl.pl By the given diagram. Wific for 020; it is pure clay the Nc2517 Ny=1 Cu = 1200 ra Ny = 0 BC equatin is u = Caleto Ng, df +48 B. NZ 'Sg .:9 = 1200(517) +121(1)(2) +0 Tahu 7082 lb / f12 | 7082 allowable fis 3 Vallowable. = 2360.6 lb) 442 (b) Two layer system Cu = | 1200 X2 + 800X57 Cu = 914128 lb / H² is Y = 914,28(517) +121(2)(1) to du 54514 16 141²7 / allowable - FS 545314 = 1817.5 lb / 4² Yallowable = 1818 eb/