DHARMSHEARING STRENGTH OF SOILS 317
of the box was 3600 mm^2 , and the normal load was 540 N what would have been the failure shear
stress?
8.25 Pore pressure measurements were made during undrained triaxial tests on samples of com-
pacted fill material from an earth dam after saturating them in the laboratory. The results were
as follows:
Property measured kN/m^2 I Test II Test
Lateral pressure (σ 3 ) 150 450
Total vertical pressure (σ 1 ) 400 1000
Pore water pressure (u) 30 125
Determine the apparent cohesion and the angle of shearing resistance as referred to (i) total
stress and (ii) effective stress. (S.V.U.—B.E. (R.R.)—Sept. 1978)
8.26 The following result were obtained from a series of undrained triaxial tests carried out on undis-
turbed samples of soil.
Cell pressure (kN/m^2 ) Additional axial load at failure (N)
200 270
400 330
600 390
Each sample, originally 36 mm diameter and 72 mm high, had a vertical deformation of 5.4 mm.
Determine total stress parameters.
8.27 For a normally consolidated insensitive clay φCID = 30°. Deviator stress at failure of the same soil
is 250 kN/m^2 in CIU test. If Skempton’s A-parameter at failure is 0.62, find out φCIU for this soil.
Also, find out the confining pressure during the consolidation state.
(S.V.U.—B.Tech. (Part-time)—April, 1982)