Soil Mechanics and Foundation Engineering MCQ Questions & Answers

Soil Mechanics and Foundation Engineering MCQs : This section focuses on the "Soil Mechanics and Foundation Engineering". These Multiple Choice Questions (MCQs) should be practiced to improve the Soil Mechanics and Foundation Engineering skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.

Question 1

A coarse-grained soil has a voids ratio 0.75, and specific gravity as 2.75. The critical gradient at which quick sand condition occurs, is

A. 0.25
B. 0.5
C. 0.75
D. 1

Question 2

A compacted soil sample using 10% moisture content has a weight of 200 g and mass unit weight of 2.0 g/cm3. If the specific gravity of soil particles and water are 2.7 and 1.0, the degree of saturation of the soil is

A. 11.10%
B. 55.60%
C. 69.60%
D. none of these.

Question 3

A partially saturated sample of soil has a unit weight of 2.0 g/cm3 and specific gravity of soil particles is 2.6. If the moisture content in the soil is 20%, the degree of saturation is

A. 20%
B. 77%
C. 92%
D. none of these.

Question 4

A soil has bulk density 2.30 g/cm3 and water content 15 per cent, the dry density of the sample, is

A. 1.0 g/cm2
B. 1.5 g/cm3
C. 2.0 g/cm3
D. 2.5 g/cm3

Question 5

According to Coulomb's wedge theory, the active earth pressure slides the wedge

A. down and outwards on a slip surface
B. up and inwards on a slip surface
C. horizontal upward and parallel to base
D. horizontal inward and parallel to base.

Question 6

Accurate determination of water content, is made by

A. calcium carbide method
B. sand bath method
C. alcohol method
D. oven-drying method.

Question 7

Back fill with a sloping surface exerts a total active pressure Pa on the wall of height H and acts at

A. H/4 above the base parallel to base
B. H/2 above the base parallel to base
C. H/3 above the base parallel to base
D. H/5 above the base parallel to base.

Question 8

Degree of saturation of a natural soil deposit having water content 15%, specific gravity 2.50 and void ratio 0.5, is

A. 50%
B. 60%
C. 75%
D. 80%

Question 9

Factor of safety against sliding of a slope, is the ratio of

A. actual cohesion to that required to maintain stability of slope
B. shear strength to shear stress along the surface
C. neither (a) nor (b)
D. both (a) and (b).

Question 10

Failure of the stability of slopes, generally occurs along

A. slip plane
B. a horizontal surface
C. a curved surface
D. all the surfaces.

Question 11

Geologic cycle for the formation of soil, is

A. Upheavel → transportation → deposition → weathering
B. Weathering → upheaval → transportation → deposition
C. Transportation → upheaval → weathering → deposition
D. Weathering → transportation → deposition → upheaval

Question 12

If the failure of a finite slope occurs through the toe, it is known as

A. slope failure
B. face failure
C. base failure
D. toe failure.

Question 13

In a liquid limit test, the moisture content at 10 blows was 70% and that at 100 blows was 20%. The liquid limit of the soil, is

A. 35%
B. 50%
C. 65%
D. none of these.

Question 14

Minimum size of the particles of silt soil, is

A. 0.002 mm
B. 0.04 mm
C. 0.06 mm.
D. 0.08 mm

Question 15

Pick up the clay soil group which does not swell when wet from the following :

A. Kaolinite group
B. Illite group
C. Vermiculite group
D. Montrorillonite group.

Question 16

Pick up the correct statement from the following:

A. When water table is above the base of a footing, the dry weight m should be used for soil below water table
B. When water table is located somewhat below the base of a footing, the elastic wedge is partly of moist soil and partly of submerged soil, and a suitable reduction factor is used
C. When water table is just at the base of the footing, no reduction factor is used
D. None of these.

Question 17

Pick up the correct statement from the following:

A. Sandy clayloam contains highest percentage of sand
B. Silty clayloam contains highest percentage of silt
C. Stiff boulder clay offers maximum shear strength
D. Soft chalk carries least safe load

Question 18

Pick up the correct statement from the following:

A. Failure plane carries maximum shear stress
B. Failure plane does not carry maximum shear stress
C. Failure plane carries shear stress equal to maximum shear stress
D. None of these.

Question 19

The active earth pressure of a soil is proportional to (where φ is the angle of friction of the soil)

A. tan (45° - φ)
B. tan2 (45° + φ/2)
C. tan2 (45° - φ/2)
D. tan (45° + φ)

Question 20

The coefficient of compressibility of soil, is the ratio of

A. stress to strain
B. strain to stress
C. stress to settlement

Question 21

The effective size of particles of soil is denoted by

A. D10
B. D20
C. D30
D. D60

Question 22

The internal molecular attraction of a soil, the cohesion

A. decreases as the moisture content increases
B. increases as the moisture content decreases
C. is more in well compacted clays
D. depends upon the external applied load.

Question 23

The lateral earth pressure on a retaining wall

A. is equal to mass of the soil retained
B. proportional to the depth of the soil
C. proportional to the square of the depth of the soil
D. proportional to the internal friction of the soil

Question 24

The liquid limit and plastic limit exist in

A. sandy soils
B. silty soils
C. gravel soils
D. clay soils.

Question 25

The liquidity index is defined as a ratio expressed as percentage of

A. plastic limit minus the natural water content, to its plasticity index
B. natural water content minus its plastic limit to its plasticity index
C. natural water content plus its plastic limit to its plasticity index
D. liquid limit minus the natural water content to the plasticity index.

Question 26

The maximum value of effective stress in the past divided by the present value, is defined as over consolidation ratio (OCR). The O.C.R. of an over consolidated clay is

A. less than 1
B. 1
C. more than 1
D. None of these.

Question 27

The minimum water content at which the soil just begins to crumble when rolled into threads 3 mm in diameter, is known

A. liquid limit
B. plastic limit
C. shrinkage limit
D. permeability limit.

Question 28

The minimum water content at which the soil retains its liquid state and also possesses a small shearing strength against flowing, is known

A. liquid limit
B. plastic limit
C. shrinkage limit
D. permeability limit.

Question 29

The quantity of seepage of water through soils is proportional to

A. coefficient of permeability of soil
B. total head loss through the soil
C. neither (a) nor (b)
D. both (a) and (b).

Question 30

The ratio of the volume of voids to the volume of soil solids in a given soil mass, is known

A. porosity
B. specific gravity
C. void ratio
D. water content.

Question 31

The ratio of the weight of given volume of soil solids to the weight of an equal volume of distilled water at the given temperature, is known

A. porosity
B. specific gravity
C. void ratio
D. water content.

Question 32

The relationship between void ratio (e) and porosity ratio (n) is :

A. n =
B. e =
C. n =
D. e = n/(1 - n)

Question 33

The seepage force in a soil, is

A. perpendicular to the equipotential lines
B. proportional to the exit graident
C. proportional to the head loss
D. all the above.

Question 34

The ultimate Settlement of a soil is directly proportional to:

A. depth of the compressible soil strata
B. compressive index
C. void ratio
D. both (a) and (b)

Question 35

The water content of soil is defined as the ratio of

A. volume of water to volume of given soil
B. volume of water to volume of voids in soil
C. weight of water to weight of air in voids
D. weight of water to weight of solids of given mass of soil.

Question 36

The weight of a pycnometer containing 400 g sand and water full to the top is 2150 g. The weight of pycnometer full of clean water is 1950 g. If specific gravity of the soil is 2.5, the water content is

A. 5%
B. 10%
C. 15%
D. 20%

Question 37

Under-reamed piles are generally

A. driven piles
B. bored piles
C. precast piles
D. all the above.

Question 38

When drainage is permitted under initially applied normal stress only and full primarily consolidation is allowed to take place, the test is known as

A. quick test
B. drained test
C. consolidated undrained test
D. none of these.