Soil Mechanics and Foundations MCQ Questions and Answers in Civil Engineering

Question. The ratio of the volume of air voids to the volume of voids, is called ?
a) void ratio
b) air content
c) degree of saturation
d) porosity

Answer : B

Question. The change in volume of soil per unit of initial volume due to a given unit increase in pressure is called ?
a) coefficient of permeability
b) coefficient of compressibility
c) coefficient of volume compressibility
d) coefficient of curvature

Answer : C

Question. The critical height in the stability of soil is the ?
a) minimum height at which it is possible for the sloped bank of soil to be stable
b) maximum height at which it is possible for the sloped bank of soil to be stable
c) minimum vertical height of the soil in an open excavation
d) maximum vertical height of the soil is an open excavation

Answer : B

Question. Flow lines and equipotential lines are ?
a) perpendicular to each other
b) parallel to each other
c) intersecting lines at 90° to each other
d) intersecting lines at 45° to each other

Answer : C

Question. The smallest sieve size according to Indian standards is ?
a) 0.0045 mm
b) 0.045 mm
c) 0.45 mm
d) 0.154 mm

Answer : B

Question. The consolidation of a soil is defined as the ?
a) process of compression by gradual reduction of pore space under steady load
b) process which gives gradual decrease of water content at constant load
c) change in volume of soil due to expulsion of pure water under an applied load
d) any one of the above

Answer : D

Question. Which of the following statement is correct ?
a) The settlement of a flexible footing on cohesionless soil is less in the centre than at the edges
b) The settlement of a rigid footing on cohesionless soil is uniform throughout
c) The settlement of a flexible footing on cohesive soil is more in the centre than at the edges
d) all of the above

Answer : D

Question. The coefficient of earth pressure at rest for stiff clay is about ?
a) 0.4
b) 0.5
c) 0.6
d) 0.8

Answer : D

Question. Toughness index is the ratio of ?
a) flow index and plasticity index
b) plasticity index and flow index
c) liquidity index and flow index
d) flow index and liquidity index

Answer : B

Question. The useful method of finding the shear strength of very plastic cohesive soils is by means of ?
a) cone test
b) penetration test
c) vane shear test
d) torsional shear test

Answer : C

Question. If the pores of a soil are completely full of air only, the soil is said to be ?
a) wet soil
b) dry soil
c) fully saturated soil
d) partially saturated soil

Answer : B

Question. The coefficient of consolidation is used for evaluating ?
a) stress in the soil
b) total settlement
c) over consolidation ratio
d) time rate of settlement

Answer : D

Question. The approximate void ratio in sandy soils is ?
a) 0.2
b) 0.6
c) 0.8
d) 1.2

Answer : B

Question. The equipotential line in a seepage through a soil medium is defined as the ?
a) path of particles of water through a saturated soil mass
b) line connecting points of equal head of water
c) flow of movement of fine particles of soil
d) direction of the flow particle

Answer : B

Question. The hydraulic gradient provided at the downstream side of a hydraulic structure such as a dam is called ?
a) downstream gradient
b) tail water gradient
c) exit gradient
d) any one of these

Answer : D

Question. The average velocity of flow that will take place through the total cross-sectional area of soil under unit hydraulic gradient is called ?
a) uniformity coefficient
b) Darcy's coefficient
c) coefficient of permeability
d) terminal velocity

Answer : C

Question. Soils are derived from ?
a) igneous rocks
b) sedimentary rocks
c) metamorphic rocks
d) any one of these

Answer : D

Question. The rate of expulsion of pore fluid is directly dependent on the ............. ?
a) shear strength
b) void ratio
c) permeability
d) none

Answer : C

Question. The unit weight of a soil at zero air voids depends upon ?
a) unit weight of water
b) water content
c) specific gravity
d) all of these

Answer : D

Question. A line showing the dry density as a function of water content for soil containing no air voids, is called ?
a) saturation line
b) zero air void line
c) liquid limit line
d) none of these

Answer : A

Question. The frictional resistance of clayey soil is ......... sandy soil ?
a) less than
b) more than
c) same as
d) None of these

Answer : A

Question. The density of sand at which there is no change in volume under the influence of shearing strain produced due to shear stress, is called ?
a) relative density
b) apparent density
c) critical density
d) any of these

Answer : C

Question. Stoke's law is applicable to particles upto ............. effective diameter ?
a) 0.0002 mm
b) 0.002 mm
c) 0.02 mm
d) 0.2 mm

Answer : A

Question. If a shear stress is applied on a dense sand, the shear strain caused will ........ the volume of sand ?
a) increase
b) decrease
c) not effect
d) none

Answer : A

Question. The degree of saturation for fully saturated soil is ?
a) 0.25
b) 0.50
c) 0.75
d) 1

Answer : D

Question. According to Terzaghi's equation, the bearing capacity of strip footing resting on cohesive soil (c=10 kN/m²) per unit depth and unit width (assume N, as 5.7) is ?
a) 47 kN/m²
b) 57 kN/m²
c) 67 kN/m²
d) 77 kN/m²

Answer : B

Question. The angle of internal friction of round-grained loose sand is about ?
a) 5° to 25°
b) 25? to 30?
c) 30° to 35?
d) 32? to 37?

Answer : B

Question. When the water table is close to the ground surface, the bearing capacity of a soil is reduced to ?
a) one-fourth
b) one-half
c) two-third
d) three-fourth

Answer : B

Question. The seepage force in soils is ?
a) proportional to head loss
b) proportional to exit gradient
c) perpendicular to the equipotential lines
d) all of these

Answer : D

Question. Gravel and sand is a ?
a) cohesive coarse grained soil
b) cohesive line grained soil
c) non-cohesive coarse grained soil
d) non-cohesive fine grained soil

Answer : C

Question. The ratio of the difference between the voids ratio in its loosest state and its natural void ratio to the difference between the void ratio is the loosest and densest state, is called ?
a) density index
b) relative density
c) degree of density
d) any one of these

Answer : D

Question. The shrinkage index is equal to ?
a) liquid limit + plastic limit
b) plastic limit - liquid limit
c) liquid limit - shrinkage limit
d) shrinkage limit - liquid limit

Answer : C

Question. The time factor for a clay layer is ?
a) a dimensionless parameter
b) directly proportional to permeability
c) directly proportional to drainage
d) none of these

Answer : B

Question. The active earth pressure of a soil is defined as the lateral pressure exerted by soil ?
a) when it is at rest
b) when the retaining wall has no movement relative to the back fill
c) when the retaining wall tends to move away from the back fill
d) when the retaining wall moves into the soil

Answer : C

Question. The bearing capacity factors Nc, Nq, and N?, are functions of ?
a) cohesion of the soil
b) friction angle
c) internal friction angle
d) both (a) and (b)

Answer : C

Question. The liquid limit minus plastic limit is termed as ?
a) flow index
b) plasticity index
c) shrinkage index
d) liquidity index

Answer : D

Question. According to Stoke's law, the velocity at which grains settle out of suspension, all other factors being equal, is dependent upon ?
a) shape of the grain
b) weight of the grain
c) size of the grain
d) all of these

Answer : D

Question. The bearing capacity of a soil depends upon ?
a) grain size of the soil
b) size of the footing
c) shape of the footing
d) all of these

Answer : D

Question. The critical gradient of the seepage of water ?
a) directly proportional to void ratio
b) increases with the decrease in void ratio
c) inversely proportional to specific gravity
d) increases with the decrease in specific gravity of soil

Answer : B

Question. The void ratio for saturated soil is equal to the ........... of water content and specific of solids ?
a) sum
b) difference
c) product
d) ratio

Answer : C

Question. The ultimate settlement of a soil ?
a) is directly proportional to the compression index
b) decreases with an increase in the initial void ratio
c) is directly proportional to the depth of the compressible soil mass
d) all of the above

Answer : D

Question. The strength of a soil is usually identified by ?
a) direct tensile stress
b) direct compressive stress
c) ultimate shear stress
d) effective stress

Answer : C

Question. Chemical weathering of soil is caused due to ?
a) oxidation
b) hydration
c) carbonation and leaching
d) all of these

Answer : D

Question. The quantity of seepage of water in a soil medium is ?
a) directly proportional to the head of water at upstream
b) inversely proportional to the head of water at upstream
c) directly proportional to the coefficient of permeability
d) inversely proportional to the coefficient of permeabilit

Answer : C

Question. The contact pressure of rigid footing on cohesive soils is ?
a) more in the centre than at the edges
b) less in the centre than at the edges
c) uniform throughout
d) none of these

Answer : B

Question. When the plastic limit is equal to or greater than the liquid limit, then the plasticity index is ?
a) negative
b) zero
c) one
d) more than one

Answer : B

Question. The coefficient of passive earth pressure ........ with the increase of angle of shearing resistance
a) increases
b) decreases
c) does not change
d) Any of the above

Answer : A

Question. Black cotton soil ?
a) is inorganic in nature
b) contains large percentage of clay mineral
c) exhibits high compressibility
d) all of these

Answer : D

Question. A soil is in a semi-solid state, if the consistency index is ?
a) zero
b) one
c) more than unity
d) none of these

Answer : C

Question. For a sandy soil, the angle of internal friction is 30°. If the major principal stress is 50 kN/m² at failure, the corresponding minor principal stress will be ?
a) 12.2 kN/m²
b) 16.66 kN/m²
c) 20.8 kN/m²
d) 27.2 kN/m²

Answer : B

Question. The unit bearing capacity of footing in sand ?
a) decreases with depth of footing
b) decreases with width of footing
c) increases as well as decrease with depth of footing
d) increases with width of footing angle of internal friction

Answer : D

Question. The decrease in voids ratio per unit increase of pressure is called ?
a) coefficient of permeability
b) coefficient of compressibility
c) coefficient of volume compressibility
d) coefficient of

Answer : B

Question. The maximum unit pressure that a soil can withstand without rupture in shear or without excessive settlement of the structure, is called ?
a) allowable bearing pressure
b) safe bearing capacity
c) ultimate bearing capacity
d) bearing capacity

Answer : D

Question. The liquid limit exists in ?
a) sandy soils
b) gravel soils
c) silty soils
d) silty soils

Answer : C

Question. The property of the soil mass which permits the seepage of water through its interconnection voids, is called ?
a) capillarity
b) permeability
c) porosity
d) none of these

Answer : B

Question. The compression index of the soil ?
a) increases with the increase in liquid limit
b) decreases with the increase in liquid limit
c) increases with the decrease in plastic limit
d) decreases with the increase in plastic limit

Answer : A

Question. The ratio of the volume of voids to the total volume of soil mass is called ?
a) water content ratio
b) porosity
c) void ratio
d) degree of saturation

Answer : B

Question. If the volume of voids is equal to the volume of soil solids, then the values of porosity and ratio are respectively ?
a) 0 and 0.5
b) 0 and 1
c) 0.5 and 1
d) 1 and 0.5

Answer : C

Question. The property of a soil which is of great importance in finding settlement of structures, is
a) permeability
b) shear strength
c) consolidation
d) compressibility

Answer : C

Question. Residual soils are ?
a) sands
b) silts
c) clays
d) all of these

Answer : D

Question. The neutral stress is ?
a) transmitted through the points of contact of the interconnected particles of soil
b) transmitted to the soil base through the pore water
c) independent of the depth of water above the soil mass
d) due to weight of soil particles

Answer : B

Question. The frictional resistance offered by sand is ?
a) sliding friction
b) rolling friction
c) resistance due to interlocking
d) all of these

Answer : D

Question. The ratio of settlement at any time (t) to the final settlement is known as ?
a) compression index
b) coefficient of consolidation
c) degree of consolidation
d) none of these

Answer : C

Question. Mechanical weathering of soils is caused by ?
a) periodical temperature changes
b) splitting action of flowing water
c) splitting action of ice
d) all of these

Answer : D

Question. The settlement of a footing in sand depends upon the ?
a) stress deformation characteristics of sand
b) relative density of the sand
c) width of the footing
d) all of these

Answer : D

Question. The minimum size of grains of silts is about ?
a) 0.0002 mm
b) 0.002 mm
c) 0.02 mm
d) 0.2 mm

Answer : A

Question. A sample of soil has liquid limit 45 %, plastic limit 25 %, shrinkage limit 17 % and natural moisture content 30%. The consistency index of the soil is ?
a) 15/20
b) 13/20
c) 8/20
d) 5/20

Answer : A

Question. The permissible exit gradient for safety against piping which endanger stability of a hydraulic structure, should be ?
a) 0.2
b) 0.4
c) 0.6
d) 0.8

Answer : A

Question. When applying Darcy's law to soils, it is assumed that the ?
a) soil is incompressible
b) soil is homogeneous and isotropic
c) flow conditions are laminar
d) all of these

Answer : D

Question. The coefficient of consolidation is measured ?
a) cm²/g
b) cm²/s
c) g/cm²/s
d) cm²/g/s

Answer : B

Question. The void ratio of a soil is defined as the ratio of the ?
a) weight of water to the weight of solids
b) volume of water to the volume of voids in the soil mass
c) total volume of voids to the volume of soil solids
d) total volume of voids to the total volume of soil

Answer : C

Question. The plastic limit of a soil is defined as the ?
a) limit of water that makes the soil to flow
b) amount of water content which makes the soil to go into the liquid state
c) amount of water content which makes the soil to go into the solid state from the liquid state
d) minimum amount of water content which makes the soil to be rolled into 3 mm diameter threads

Answer : D

Question. The piping failure in a hydraulic structure can be prevented by ?
a) diverting the seepage water into filter wells
b) increasing the creep length of flow of water
c) increasing the stress due to weight of the structure
d) all of the above

Answer : D

Question. A sample of clay and a sample of sand have the same specific gravity and void ratio. Their permeabilities will differ because ?
a) their porosities will be different
b) their densities will be different
c) their degrees of saturation will be different
d) the size ranges of their voids will be different

Answer : D

Question. The soil transported by wind is called ?
a) aeolian soil
b) marine soil
c) alluvial soil
d) lacustrine soil

Answer : A

Question. A fine grained soil ?
a) has low permeability
b) has high compressibility
c) may or may not be plastic
d) all of these

Answer : D

Question. If the soil below the base of the footing is dry or moist, the confining pressure is approximately .......... the confining pressure available when the water table is at the base of the footing ?
a) equal to
b) double
c) three times
d) four times

Answer : B

Question. The maximum water content of a saturated soil at which a reduction in its moisture does not cause a decrease in volume of the soil, is called ?
a) liquid limit
b) plastic limit
c) elastic limit
d) shrinkage limit

Answer : D

Question. When the particles of soil are oriented 'edge to edge' or 'edge to face' with respect to another, the soil is said to have ?
a) single grained structure
b) double grained structure
c) honey-combed structure
d) flocculent structure

Answer : D

Question. The maximum size of grains of silts is about ?
a) 0.06 mm
b) 0.2 mm
c) 0.5mm
d) 1 mm

Answer : A