GN6002_Civil_engineering _Soil_Mechanics_and_Foundation

The hydraulic head that would produce a quick condition in a sand stratum of thickness 1.5 m, specific gravity 2.67 and voids ratio 0.67 is equal to

• 1.5m

• 1m

• 2m

• 2.5m

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

• 2 months

• 3 months

• 6 months

• 2.5 months

Degree of consolidation is

• Select the correct range of density index, 1D

• directly proportional to time and inversely proportional to drainage path

• directly proportional to time and inversely proportional to square of drainage path

• directly proportional to drainage path and inversely proportional to time

Select the correct range of density index, 1D

• 0<1D

• 0<1D<1

• 0>1D

• 0=1D

For a loose sand sample and a dense sand sample consolidated to the same effective stress

• ultimate strength is different but peak strength is same

• ultimate strength is same but peak strength of dense sand is greater than that of loose sand

• ultimate strength is same and also peak strength is same

• ultimate strength is same but peak

Within the consolidation process of a saturated clay

• both neutral pressure and effective pressure decrease

• a gradual decrease in neutral pressure and a gradual increase in effective pressure takes place and sum of the two is constant

• both neutral pressure and effective pressure increase

• a gradual increase in neutral pressure and a gradual decrease in effective pressure takes place and sum of the two is constant

Rise of water table in cohesionless soils upto ground surface reduces the net ultimate bearing capacity approximately by

• 45%

• 30%

• 50%

• 75%

Terzaghi's bearing capacity factors Nc, Nq and Nr are functions of

• none of the above

• cohesion only

• both cohesion and angle of internal friction

• angle of internal friction only

Valid range for S, the degree of saturation of soil in percentage is

• S>0

• 0<S<100

• 0≤S≤100

• S<0

If the natural water content of soil mass lies between its liquid limit and plastic limit, the soil mass is said to be in

• Plastic State

• Liquid state

• Solid state

• None