Subjective questions:
1. How are soils formed in nature? Write down the types of soils based upon their origins. [5]
2. What are the most commonly found soil grain structures? Describe with neat sketches. [5]
3. Explain the three phase system of soil in brief. [3]
4. Establish a relation between void ratio, specific gravity, degree of saturation and water content
of soil along with their respective definitions. [5]
5. Write in short about atterberg’s limits. [3]
6. Why is it necessary to classify the soils? Also write down the methods used for soil classification
in engineering. [5]
7. Explain in brief the types of water found in the soils. [3]
8. Write short notes on Terzaghi’s effective stress principle. [5]
9. What do you mean by quick sand condition? Derive an expression for the critical hydraulic
gradient of soil. [3+5]
10. State and explain darcy’s law of permeability. [3]
11. Describe the factors affecting the permeability of soil. [5]
12. What are the various problems occurred due to seepage of water through the soil? [5]
13. Explain in short about seepage through earthen structures. [5]
14. Define compaction of soil. Why is it necessary to compact the soils? Also specify the types of
structures for which compaction of soil is necessary. [5]
15. Differentiate between compaction and consolidation. Give examples. [5]
16. What is compaction curve? Give its salient features. What is zero air void line? [5]
17. What are the factors affecting compaction of soil? Describe in brief. [5]
18. Establish a relation between dry density and moisture content of a soil. [5]
19. What are the different types of compaction methods adopted in field? How would you select
the type of roller to be used? [5]
20. Define shear strength of soil. Write in short about Mohr-Coulomb failure theory. [5]
21. What are the different types of earth pressures? Give examples. [5]
22. Write down the assumptions for Rankine’s earth pressure theory. [5]
23. Derive an expression for active earth pressure in a cohesion less soil. [5]
24. Derive an expression for active earth pressure in a cohesive soil. [5]
25. What do you mean by critical height of a cohesive soil? Derive an expression for it. [5]
26. What are the different types of bearing capacities of soil? Also specify which one of them is used
for foundation design? [5]
27. Write in short about floating / compensating foundation. [3]
28. What are the assumptions made in Terzaghi’s bearing capacity theory? [5]
29. Explain Terzaghi’s general bearing capacity theory. [5]
30. Describe with sketches the principal modes of foundation failures. [5]
31. Does water table has any effect on bearing capacity of a soil? Explain. [5]
32. What are the factors that govern bearing capacity of a foundation? [5]
33. What is the purpose of a foundation? Also explain the various types of foundations used in civil
engineering? [5]
34. If you were asked to design the foundation of a multi-storied commercial building, which type of
foundation would you use? Explain with reasons. [5]
35. A sample of soil of volume 300 cc weighed 600gms in its natural state. When it was oven dried,
its weight reduced to 500 gms. Take specific gravity of soil solids = 2.7 and density of water =
1gm/cc and determine the following: [10]
a. Water content.
b. Void ratio
c. Degree of saturation
d. Porosity
36. Calculate the load in Kilo Newtons that can be safely carried by a square isolated footing having
size of 4m founded at a depth of 2m below the ground level. The soil is a clay having bulk unit
weight of 18 𝑘𝑁/𝑚3, cohesive strength 𝑐 = 15 𝑘𝑁/𝑚2 . Take 𝑁𝑐 = 5.7 and FOS = 3. [10]
Ans: 1123.2 kN
37. In a cylindrical sample of coarse sand 15cm high and 5cm in diameter when tested in a
constant head permeameter, water permeated through the soil under a constant
hydrostatic head of 50cm and 500 gms of water was collected in a jar in 6 seconds.
Based on the given data, find the co-efficient of permeability of the soil in cm/sec. [5]
38. Determine the safe size of a square isolated foundation required for a residential building which
carries a maximum column load of 750 kN and the foundation is backfilled. The foundation is to
be laid below 1.5 m from the ground surface on a sandy soil having water table at a depth of 1 m
from the ground surface. Take ∅ = 30° 𝛾 = 18 𝑘𝑁/𝑚3 𝑎𝑛𝑑 𝛾𝑠𝑎𝑡 = 19.93 𝑘𝑁/𝑚3 and FOS = 3.
[10]. Ans: B=2m.
