Soil Mechanics and Foundation Engineering MCQs Archives

21. If the material of the base of the Casagrande liquid limit device on which the cup containing soil paste drops is softer than the standard hard rubber, then______________?

A. the liquid limit of soil always increases

B. the liquid limit of soil always decreases

C. the liquid limit of soil may increase

D. the liquid limit of soil may decrease

✅ The correct answer is option A.

22. The total discharge from two wells situated near to each other is_________________?

A. sum of the discharges from individual wells

B. less than the sum of the discharges from individual wells

C. greater than the sum of the discharges from individual wells

D. equal to larger of the two discharges from individual wells

✅ The correct answer is option B.

23. The average coefficient of permeability of natural deposits________________?

A. parallel to stratification is always greater than that perpendicular to stratification

B. parallel to stratification is always less than that perpendicular to stratification

C. is always same in both directions

D. parallel to stratification may or may not be greater than that perpendicular to stratification

✅ The correct answer is option A.

24. If the shearing stress is zero on two planes, then the angle between the two planes is________________?

A. 45°

B. 90°

C. 135°

D. 225°

✅ The correct answer is option B.

25. 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

✅ The correct answer is option A.

26. The total and effective stresses at a depth of 5 m below the top level of water in a swimming pool are respectively__________________?

A. zero and zero

B. 0.5 kg/cm2 and zero

C. 0.5 kg/cm2 and 0.5 kg/cm2

D. 1.0 kg/cm2 and 0.5 kg/cm2

✅ The correct answer is option B.

27. In a consolidated drained test on a normally consolidated clay, the volume of the soil sample during shear________________?

A. decreases

B. increases

C. remains unchanged

D. first increases and then decreases

✅ The correct answer is option A.

28. When the plastic limit of a soil is greater than the liquid limit, then the plasticity index is reported as_____________?

A. negative

B. zero

C. non-plastic (NP)

D. 1

✅ The correct answer is option B.

29. The flownet for an earthen dam with 30 m water depth consists of 25 potential drops and 5 flow channels. The coefficient of permeability of dam material is 0.03 mm/sec. The discharge per meter length of dam is________________?

A. 0.00018 nrVsec

B. 0.0045 m3/sec

C. 0.18m3/sec

D. 0.1125m3/sec

✅ The correct answer is option A.

30. 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

✅ The correct answer is option B.