Civil Engineering - Soil Mechanics and Foundation Engineering MCQs Part 3

1. The vane shear test is used for the in-situ determination of the undrained strength of the intact fully saturated

A.
sands

B.
clays

C.
gravels

D.
highly organic soils.

 Answer Option B

2. Fundamental relationship between dry density (γd), bulk density (γ) and water content (ω), is :

A.
γ =

B.
γd =

C.
ω =

D.
ω =

 Answer Option B

3. The specific gravity of quartz, is

A.
2.65

B.
2.72

C.
2.85

D.
2.90

 Answer Option A

4. If the cohesive force, (c), is 1.5 t/m2, the density (γ) of the soil is 2.0 t/m3, factor of safety (F) is 1.5 and stability factor (Sn) is 0.05, the safe height of the §lope, is

A.
5 metres

B.
8 metres

C.
10 metres

D.
12 metres

 Answer Option C

5. Pick up the correct statement from the following:

A.
The phenomenon of quicksand generally occurs in the cohesionless soil

B.
At critical hydraulic gradient, the saturated sand becomes quick

C.
The critical gradient depends on the void ratio and the specific gravity

D.
The quick sand occurs more in fine sand and silt than coarse material

E.
All the above.

 Answer Option E

6. If W1, W2, W3 and W4 are the sequential weights obtained during observations in pycnometer method for determining water content, the formula to be used, is

A. W =

B. W =

C. W =

D. W =

 Answer Option C

7. Si particles

A. show dilatancy

B. swell when moist

C. possess high strength when dry

D. disintegrate easily.

 Answer Option A

8. Flow net is used for the determination of

A. quantity of seepage

B. hydrostatic pressure

C. seepage pressure

D. exit gradient

E. all the above.

 Answer Option E

9. If the back fill is having a uniform surcharge of intensity q per unit area, the lateral pressure will be

A. q times the lateral pressure within the surface

B. 1/q times the lateral pressure within the surface

C. equal to a fill of height Z equal to q/r, where r is the density of the backfill

D. none of these.

 Answer Option C

10. Pick up the correct statement from the following:

A. Isotropic consolidation of clay can be obtained in the triaxial apparatus under equal all-round pressure.

B. If the present effective stress is the maximum to which the clay has ever been subjected, it is called normally consolidated clay

C. If the present effective stress in the past was more than present effective stress, it is called over-consolidated clay

D. All the above.

 Answer Option D

11. Through a point in a loaded soil, the principal stress is maximum on

A. minor principal plane

B. intermediate principal plane

C. major principal plane

D. none of these.

 Answer Option C

12. Maximum size of clay particles, is :

A. 0.002 mm

B. 0.04 mm

C. 0.06 mm

D. 0.08 mm

E. 1 mm

 Answer Option A

13. The capillary rise of water

A. depends upon the force responsible

B. increases as the size of the soil particles increases

C. decreases as the size of the soil particles decreases

D. is less in wet soil than in dry soil.

 Answer Option A

14. Coulomb's wedge theory assumes that

A. back fill is dry, cohesionless, homogeneous and isotropic

B. slip surface is the plane which passes through the heel of the wall

C. sliding wedge itself acts as a rigid body and the value of earth pressure is obtained by considering the limiting equilibrium of the wedge

D. position and direction of the resultant earth pressure, are known

E. all the above.

 Answer Option E

15. If dry density, water density and specific gravity of solids of a given soil sample are 1.6 g/cc, 1.84 g/cc and 2.56 respectively, the porosity of the soil sample, is

A. 0.375

B. 0.370

C. 0.380

D. 0.390

 Answer Option A

16. Pick up the correct statement applicable to plate load test

A. Width of the test pit for plate load test is made five times the width of the plate

B. At the centre of the test pit, a hole is dug out whose size is kept equal to the size of the test plate

C. Bottom level of the hole dug at the centre of the test pit, is kept at the level of the actual formation

D. Ratio of the depth of the hole to the width of the test plate is the same as the ratio of the depth of the actual formation to the width of the formation

E. All the above.

 Answer Option E

17. Terzaghi's analysis assumes :

A. soil is homogeneous and isotropic

B. elastic zone has straight boundaries inclined at ψ = φ to the horizontal and plastic zones fully developed

C. failure zones do not extend above the horizontal plane through the base of the footing

D. all the above.

 Answer Option D

18. The fundamental equation of air content (ac), degree of saturation (Sr) and void ratio (e), is

A. ac =

B. ac =

C. ac =

D. ac = 1 + e/Sr

 Answer Option C

19. A soil sample has passing 0.075 mm sieve = 60% liquid limit = 65% and plastic limit = 40%. The group index of the soil, is

A. 5

B. 20

C. 40

D. none of these.

 Answer Option D

20. The plasticity index is the numerical difference between

A. liquid limit and plastic limit

B. plastic limit and shrinkage limit

C. liquid limit and shrinkage limit

D. none of these.

 Answer Option A

21. The fundamental equation of specific gravity (G), dry density (γd), unit weight of water (γω) and void ratio (e), is

A. e =

B. G =

C. γd =

D. γω =

 Answer Option C

22. Negative skin friction on piles

A. is caused due to relative settlement of the soil

B. is caused in soft clays

C. decreases the pile capacity

D. all of the above.

 Answer Option D

23. The ultimate bearing capacity of a soil, is

A. total load on the bearing area

B. safe load on the bearing area

C. load at which soil fails

D. load at which soil consolidates.

 Answer Option C

24. Transporting and redepositing soils, is done by

A. water

B. glacier

C. gravity

D. wind

E. all the above.

 Answer Option E

25. A moist soil sample of volume 60 cc. weighs 108 g and its dried weight is 86.4 g. If its absolute density is 2.52, the degree of saturation is

A. 54%

B. 64%

C. 74%

D. 84%

 Answer Option D

26. Pick up the correct statement from the following:

A. O.M.C. refers to the moisture corresponding to the maximum point on the moisture content dry density curve

B. The line which shows moisture content dry density relation for soil containing a constant percentage of air voids, is known as air void line

C. The weight of hammer used for compaction test is 25 kg

D. The free fall of hammer for compaction is 30.5 cm

E. All the above.

 Answer Option E

27. The passive earth pressure of a soil, is proportional to (where φ is the angle of internal friction of the soil.)

A. tan (45° - φ)

B. tan (45° + φ)

C. tan2 (45° - φ

D. tan2 (45° + φ)

 Answer Option D

28. If a soil undergoes a change in shape and volume by application of external loads over it, but recovers its shape and volume immediately after removal of the load, the property of the soil is said to be

A. Resilience of soils

B. Elasticity of soils

C. Compressibility of soils

D. None of these.

 Answer Option B

29. If the unit weight of sand particles is 2.696 g/cc. and porosity in loose state is 44%, the critical hydraulic gradient for quick sand condition, is

A. 0.91

B. 0.92

C. 0.93

D. 0.94

E. 0.95

 Answer Option E

30. The void ratio of a soil sample decreases from 1.50 to 1.25 when the pressure is increased from 25 tonnes/m2 to 50 tonnes/m2, the coefficient of compressibility is

A. 0.01

B. 0.02

C. 0.05

D. 0.001

 Answer Option A

31. Pick up the incorrect statement from the following:

A. The smaller the size of the pores, the higher the water can rise above the water table.

B. Below the water table, the pore water may be static.

C. The hydrostatic pressure depends on the depth below the water level.

D. The attractive forces between the particles, caused due to negative pressure of water held above the water table is called soil suction.

E. None of these.

 Answer Option E

32. The maximum water content at which a reduction in water content does not cause a decrease in volume of a soil mass, is known

A. liquid limit

B. plastic limit

C. shrinkage limit

D. permeability limit.

 Answer Option C

33. A sample of saturated soil has 30% water content and the specific gravity of soil grains is 2.6. The dry density of the soil mass in g/cm3, is

A. 1.47

B. 1.82

C. 1.91

D. none of these.

 Answer Option A

34. The specific gravity of sands, is approximately

A. 1.6

B. 2.0

C. 2.2

D. 2.4

E. 2.6

 Answer Option E

35. If the coefficients of volume change and compressibility of a soil sample are respectively 6.75 x 10-2 and 3 x 10-2, the void ratio of the soil sample, is

A. 1.10

B. 1.15

C. 1.20

D. 1.25

E. 1.30

 Answer Option D

36. The minimum centre to centre distance of friction piles of 1 m diameter, is

A. 2 m

B. 2 m to 3 m

C. 3 m to 4 m

D. 5 m

 Answer Option C

37. Over-consolidation of soils is caused due to

A. erosion of over burden

B. melting of ice sheets after glaciation

C. permanent rise of water table

D. all the above.

 Answer Option D

38. Darcy's law is applicable to seepage if a soil is

A. homogeneous

B. isotropic

C. incompressible

D. all the above.

 Answer Option D

39. An infinite slope is inclined at angle i and has its angle of internal friction φ, the stability number Sa, is

A.

B.

C. (tan i - tan φ) cos2 i

D. (tan i - tan φ) sin2 i

 Answer Option C

40. Depending upon the properties of a material, the failure envelope may

A. be either straight or curved

B. pass through the origin of stress

C. intersect the shear stress axis

D. all the above.

 Answer Option D

41. A stratum of clay 2 m thick will get consolidated 80% in 10 years. For the 80% consolidation of 8 m thick stratum of the same clay, the time required is

A. 100 years

B. 120 years

C. 140 years

D. 160 years

E. 180 years.

 Answer Option D

42. The maximum net pressure intensity causing shear failure of soil, is known

A. safe bearing capacity

B. net safe bearing capacity

C. net ultimate bearing capacity

D. ultimate bearing capacity.

 Answer Option C

43. The factor which affects the compaction, is

A. moisture content

B. compacting content

C. method of compaction

D. type of soil

E. All the above.

 Answer Option E

44. The compression resulting from a long term static load and consequent escape of pore water, is known as

A. compaction

B. consolidation

C. swelling

D. none of these.

 Answer Option B

45. Soil classification of composite soils, exclusively based on the particle size distribution, is known

A. particle classification

B. textural classification

C. High Way Research Board classification

D. unified soil classification.

 Answer Option B

46. The coefficient of curvature for a well graded soil, must be between

A. 0.5 to 1.0

B. 1.0 to 3.0

C. 3.0 to 4.0

D. 4.0 to 5.0

 Answer Option B

47. Fundamental relationship between dry density (γd), specific gravity (G), water content (ω) and percentage of air voids (na) is :

A. γd =

B. γd =

C. γd =

D. γd =

 Answer Option A

48. A moist soil sample weighing 108 g has a volume of 60 cc. If water content is 25% and value of G = 2.52, the void ratio is

A. 0.55

B. 0.65

C. 0.75

D. 0.80

 Answer Option C

49. The shear resistance of a soil is con-tituted basically of the following component.

A. The frictional resistance to translocation between the individual soil particles at their contact point

B. To the structural relation to displacement of the soil because of the interlocking of the particles

C. Cohesion and adhesion between the surfaces of the soil particles

D. All the above.

 Answer Option D