RRB JE exam Civil Engineering Soil Important MCQs – 12

126.   The effect of cohesion on a soil is to
a)
 reduce both the active earth pressure intensity and passive earth pressure intensity
b)
 increase both the active earth pressure intensity and passive earth pressure intensity
c)
 reduce the active earth pressure in-tensity but to increase the passive earth pressure intensity
d)
 increase the active earth pressure in-tensity but to reduce the passive earth pressure intensity [GATE 99]
Correct Option:c

127. A retaining wall 6m high supports a backfill with a surcharge angle of 10°. The back of the wall is inclined to the vertical at a positive batter angle of 5°. If the angle of wall friction is 7°, then the resultant active earth pressure will act at a distance of 2 m above the base and inclined to the horizontal at an angle of
a)
 
b)
 10°
c)
 12°
d)
 17°
 
Correct Option:c

128. Coefficient of earth pressure at rest is
a)
 less than active earth pressure but greater than passive earth pressure
b)
 greater than active earth pressure but less than passive earth pressure
c)
 greater than  both the  active  earth pressure and passive earth pressure
d)
 less than both the active and passive earth pressures
Correct Option:b

137.   Bishop's method of stability analysis
a)
 is more conservative
b)
 neglects the effect of forces acting on the sides of the slices
c)
 assumes the slip surface as an arc of a circle
d) all of the above
Correct Option:c

138. Allowable bearing pressure for a foundation depends upon
a)
 allowable settlement only
b)
 ultimate bearing capacity of soil only
c)
 both allowable settlement and ultimate bearing capacity
d)
 none of above
Correct Option:c

142. The rise of water table below the foundation influences the bearing capacity of soil mainly by reducing
a)
 cohesion and effective angle of shearing resistance
b)
 cohesion and effective unit weight of soil
c)
 effective unit weight of soil and effective angle of shearing resistance
d)
 effective angle of shearing resistance
Correct Option:b

143. Terzaghi's general bearing capacity formula for a strip footing
(C Nc + y D Nq + 0.5 Y NTB) gives

a)
 safe bearing capacity
b)
 net safe bearing capacity
c)
 ultimate bearing capacity
d)
 net ultimate bearing capacity where C = unit cohesion
Y =unit weight of soil D = depth of foundation B = width of foundation N„ Nq, NY = bearing capacity factors

Correct Option:c

144. Terzaghi's bearing capacity factors Nc, Nq and Nr are functions of
a)
 cohesion only
b)
 angle of internal friction only
c)
 both cohesion and angle of internal friction
d) none of the above
Correct Option:b

145. In the plate loading test for determining the bearing capacity of soil, the size of square bearing plate should be
a)
 less than 300 mm
b)
 between 300 mm and 750 mm
c)
 between 750 mm and 1 m
d)
 greater than 1 m
Correct Option:b

146. Select the incorrect statement.
a)
 Bearing capacity of a soil depends upon the amount and direction of load.
b)
 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.
Correct Option:a

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/ram2. The settlement of a prototype shallow footing 1 m square under the same intensity of loading is
a)
 15 mm
b)
 between 15 mm and 25 mm
c)
 25 mm
d)
 greater than 25 mm
Correct Option:b

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
a)
 15 mm
b)
 30 mm
c) 50 mm
d)
 167 mm
Correct Option:c

149. Rise of water table in cohesionless soils upto ground surface reduces the net ultimate bearing capacity approximately by
a)
 25%
b)
 50%
c)
 75%
d)
 90%
Correct Option:b

150. Contact pressure beneath a rigid footing resting on cohesive soil is
a)
 less at edges compared to middle
b)
 more at edges compared to middle
c)
 uniform throughout
d)
 none of the above
Correct Option:b