239. Over-consolidation of soils is caused due to

A. erosion of over burden

B. melting of ice sheets after glaciations

C. permanent rise of water table

D. all the above.

240. The ratio of the undrained strength in the undrained state to the undrained strength, at the same water content, in the remoulded state, is called the sensivity of the clay. Its value for quick clays is

A.4

B.8

C.12

D.20

241. The consolidation time for soils

A. increases with increasing compressibility

B. decreases with increasing permeability

C. increases rapidly with increasing size of soil mass

D. All the above.

242. 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

243. The specific gravity of quartz, is

A.2.65

B.2.72

C.2.85

D. 2.90.

244. The specific gravity of Calcite is

A.2.65

B.2.72

C.2.85

D. 2.90.

245. The ratio of emax, and emin of silty sand, is

A.2

B.5

C.3

D. 4.0.

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