DHARM606 GEOTECHNICAL ENGINEERING14.23 What is the ultimate bearing capacity of a rectangular footing, 1.75 × 3.50 m, at a depth of 1.5 m
in a soil for which c = 30 kN/m^2 , φ = 15°, and γ = 18 kN/m^3. Brinch Hansen’s factors are Nc =
10.89, Nq = 3.94, and Nγ = 1.42. The water table is deep. The vertical load is 1500 kN and the
horizontal load is 150 kN at the base of the footing. Determine also the factor of safety.
14.24 A plate bearing test was conducted in a pure cohesive soil with 30 cm square plate at a depth of
1.5 m below the ground level. The water table was found to be at 6 m depth. Failure occurred at
a load of 50 kN. Find the factor of safety if a 1.2 m wide wall footing carriers 140 kN/m run and
the foundation is at a depth of 2 m below ground level.
(S.V.U.—B.Tech., (Part-time)—Sept., 1982)
14.25 What is the allowable load for 1.8 m square column in a dense sand (γ = 20 kN/m^3 and φ = 40°) at
a depth of 1.2 m, if the settlement is not to exceed 30 mm? Factor of safety against shear failure
is 3. Water table is at a great depth.
14.26 A 1.8 m square column is founded at a depth of 1.8 m in sand, for which the corrected N-value is
- The water table is at a detph of 2.7 m. Determine the net allowable bearing pressure for a
permissible settlement of 40 mm and a factor of safety of 3 against shear failure.
14.27 Two load tests were performed at a site-one with a 50 cm square plate and the other with a 75 cm
square plate. For a settlement of 15 mm, the loads were recorded as 50 kN and 90 kN, respec-
tively in the two tests. Determine the allowable bearing pressure of the sand and the load which
a square footing, 1.5 m size, can carry with the settlement not exceeding 25 mm.