RRB JE exam Civil Engineering Soil Important MCQs – 8

81. Degree of consolidation is
a)
 directly proportional to time and inversely proportional to drainage path
b)
 directly proportional to time and inversely proportional to square of drainage path
c)
 directly proportional to drainage path and inversely proportional to time
d)
 directly proportional to square of drainage path and inversely proportional to time
Correct Option:b

82. Time factor for a clay layer is
a)
 a dimensional parameter
b)
 directly proportional to permeability of soil
c)
 inversely proportional to drainage path
d)
 independent of thickness of clay layer
Correct Option:b

84. Clay layer A with single drainage and coefficient of consolidation Cv takes 6 months to achieve 50% consolidation. The time taken by clay layer B of the same thickness with double drainage and coefficient of consolidation Cv/2 to achieve the same degree of consolidation is
a)
 3 months
b)
 6 months
c)
 12 months
d)
 24 months
Correct Option:a

85. Coefficient of consolidation for clays normally
a)
 decreases with increase in liquid limit
b)
 increases with increase in liquid limit
c)
 first increases and then decreases with increase in liquid limit
d)
 remains constant at all liquid limits
Correct Option:a

86. Direct measurement of permeability of the specimen at any stage of loading can be made
a)
 only in fixed ring type consolido-meter
b)
 only in floating ring type consolido-meter
c)
 both (a) and (b)
d)
 none of the above
Correct Option:a

87. Compressibility of sandy soils is
a)
 almost equal to that of clayey soils
b)
 much greater than that of clayey soils
c)
 much less than that of clayey soils
d)
 none of the above
Correct Option:c

88. Select the correct statement.
a)
 coefficient of compressibility of an over-consolidated clay is less than that of a normally consolidated clay
b)
 coefficient of compressibility of an over-consolidated clay is greater than that of a normally consolidated clay
c)
 coefficient of compressibility is cons-tant for any clay
d)
 none of the above
Correct Option:a

89. Coefficient of compressibility is
a)
 constant for any type of soil
b)
 different for different types of soils and also different for a soil under different states of consolidation
c)
 different for different types of soils but same for a soil under different states of consolidation
d) independent of type of soil but depends on the stress history of soil
 
Correct Option:b

90. The ultimate consolidation settlement of a structure resting on a soil
a)
 decreases with the increase in the initial voids ratio
b)
 decreases with the decrease in the plastic limit
c)
 increases with the  increase  in the initial voids ratio
d)
 increases with the decrease in the porosity of the soil
Correct Option:a