141. The net ultimate bearing capacity of a purely cohesive soil
is independent of both depth and width of footing
142. The rise of water table below the foundation influences the bearing capacity of soil mainly by reducing cohesion and effective unit weight of soil
143. Terzaghi's general bearing capacity formula for a strip footing
ultimate bearing capacity
where C = unit cohesion
γ = unit weight of soil
D = depth of foundation
B = width of foundation
Ne, Nq, Nγ = bearing capacity factors
144. Terzaghi's bearing capacity factors Nc, Nq and Nγ are functions of
angle of internal friction only
145. In the plate loading test for determining the bearing capacity of soil, the size of square bearing plate should be between 300 mm and 750 mm
146.
a) Bearing capacity of a soil depends on the type of soil.
c) Bearing capacity of a soil depends upon shape and size of footing.
d) Bearing capacity of a soil is indepen dent of rate of loading
147. A 600 mm square bearing plate settles by 15 mm in plate load test on a cohesionless soil under an intensity of loading of 0.2 N/mm². The settlement of a prototype shallow footing 1 m square under the same intensity of loading is
between 15 mm and 25 mm
148. A 300 mm square bearing plate settles by 15 mm in a plate load test on a cohesive soil when the intensity of loading is 0.2 N/mm². The settlement of a prototype shallow footing 1 m square under the same intensity of loading is
50 mm
149. Rise of water table in cohesionless soils upto ground surface reduces the net ultimate bearing capacity approximately by 50%
150. Contact pressure beneath a rigid footing resting on cohesive soil is
more at edges compared to middle
151. According to IS specifications, the minimum depths of foundation in sand
and clay should be respectively 800 mm and 900 mm
152.The maximum differential settlement in isolated footings on clayey soils should be limited to 40 mm
153. A combined footing is generally used when number of columns is two and they are spaced close to each other
154. Negative skin friction on a pile acts downward and reduces the load
carrying capacity of the pile
155. A single acting steam hammer weighing 22.5 kN and falling through a height of 1.2 m drives a pile. If the final set is 12.5 mm, then according to Engineering News formula
allowable load for the pile is 300 kN
156. Generally the bearing capacity of a pile group is equal to the sum of bearing capacities of individual piles in case of end bearing piles
157. The settlement of a group of friction piles as compared to that of a single pile is more
158.Negative skin friction is caused by relative settlement of soil and skin
frictional resistance is caused by re lative settlement of pile.
159.a) Static formulae are suitable for friction piles driven through cohesive
soils.
c) Dynamic formulae are suitable for friction piles driven through cohesionless soils.
d) Dynamic formulae do not take into account the reduced bearing capacity
of a pile in a group
160. Mechanical stabilization of soil is done with the help of
proper grading