RRB JE exam Civil Engineering Soil Important MCQs – 9

91. The ultimate consolidation settlement of a soil is
a)
 directly proportional to the voids ratio
b)
 directly proportional to the compression index
c)
 inversely proportional to the compression index
d)
 none of the above
Correct Option:b

92. A normally consolidated clay settled 10 mm when effective stress was increased from 100 kN/m2 to 200 kN/ m2. If the effective stress is further increased from 200 kN/ m2 to 400 kN/ m2, then the settlement of the same clay is
a)
 10 mm
b)
 20 mm
c)
 40 mm
d)
 none of the above
Correct Option:a

93. Coarse grained soils are best compacted by a
a)
 drum roller
b)
 rubber tyred roller
c)
 sheep's foot roller
d)
 vibratory roller
Correct Option:d

94. With the increase in the amount of compaction energy
a)
 optimum water content increases but maximum dry density decreases
b)
 optimum water content decreases but maximum dry density increases
c)
 both optimum water content and maximum dry density increase
d)
 both optimum water content and maximum dry density decrease[ES 93]
Correct Option:b

95. The maximum dry density upto which any soil can be compacted depends upon
a)   moisture content only

b)
 amount of compaction energy only
c)
 both moisture content and amount of compaction energy
d)
 none of the above
Correct Option:c

97. For better strength and stability, the fine grained soils and coarse grained soils are compacted respectively as
a)
 dry of OMC and wet of OMC
b)
 wet of OMC and dry of OMC
c)
 wet of OMC and wet of OMC
d)
 dry of OMC and dry of OMC where OMC is optimum moisture content
Correct Option:b

98.    Select the incorrect statement.
a)
 Effective cohesion of a soil can never have a negative value.
b)
 Effective angle of internal friction for coarse grained soils is rarely below 30°.
c)
 Effective angle of internal friction for a soil increases as state of compact-ness increases.
d)
 Effective angle of internal friction is a complicated function of mineralogy and clay size content.
Correct Option:a

99. For a loose sand sample and a dense sand sample consolidated to the same effective stress
a)
 ultimate strength is same and also peak strength is same
b)
 ultimate strength is different but peak strength is same
c)
 ultimate strength is same but peak strength of dense sand is greater than that of loose sand
d) ultimate strength is same but peak
Correct Option:c

100. The shear strength of a soil
a)
 is directly proportional to the angle of internal friction of the soil
b)
 is inversely proportional to the angle of internal friction of the soil
c)
 decreases with increase in normal stress
d)
 decreases with decrease in normal stress
Correct Option:d