Capillarity in Soils

Q. Consider the following statements in the context of capillary pressure in soils:
1. Pore water pressure is negative in capillary zone.
2. Water is in tension in capillary zone.
3. Capillary pressure is more in coarse grained soils.
Which of the above statements are correct?

1. 1 and 2 only
2. 1 and 3 only
3. 2 and 3 only
4. 1, 2 and 3

Q. The void ratio of a given soil A is twice that of another soil B, while the effective size of particles of soil A is one-third of that of soil B. The ratio of height of capillary rise of water in soil A to that in soil B will be

1. 0.67
2. 1.0
3. 1.5
4. 2.0

Q. Consider the following statements:
1. Presence of moisture in sand does not affect the magnitude of friction angle.
2. Moisture introduces capillary effect in a sandy soil leading to apparent increase in angle of internal friction.
3. Moisture introduces capillary effect in a sandy soil leading to development of apparent cohesion.
4. The capillary film is broken by drying or submergence leading to loss in the apparent cohesion.
Which of these statements are correct?

1. 1, 2, 3 and 4
2. 2 and 3 only
3. 2 and 4 only
4. 3 and 4 only

Q. Which of the following statements is not true in the context of capillary pressure in soils ?

1. Water is under tension in capillary zone
2. Pore water pressure is negative in capillary zone
3. Effective stress increases due to capillary zone
4. Capillary pressure is more in coarse grained soils

Q. Statement (I): Fine-grained soils are difficult to drain.
Statement ( ll): Capillary forces act on pore water.

Directions: Each of the next items consists of two statements, one labelled as the Statement (I) and the other as Statement (II). Examine these two statements carefully and select the answers to these items using the codes given below :
Codes:

1. Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
2. Both Statement (I) and Statement (11) are individually true but Statement (II) is not the correct explanation of Statement (I)
3. Statement (I) is true but Statement (II) is false
4. Statement (I) is false but Statement (II) is true