Soil Mechanics foundation 3

 41.The active earth pressure of a soil is defined as the lateral pressure exerted by soil ?

• when it is at rest 
• when the retaining wall has no movement relative to the back fill 
• when the retaining wall tends to move away from the back fill 
• when the retaining wall moves into the soil 

42.The compression index of the soil ?

• increases with the increase in liquid limit 
• decreases with the increase in liquid limit 
• increases with the decrease in plastic limit 
• decreases with the increase in plastic limit 

43.Which of the following statement is wrong ?

• The neutral stress does not change the shearing resistance of the soil. 
• The decrease in effective stress is accompanied by increase in the neutral stress 
• The neutral stress does not decrease the void ratio 
• none of the above 

44.A flow line in seepage through a soil medium is defined as the ?

• path of particles of water through a saturated soil mass mass 
• line connecting points of equal head of water 
• flow of movement of fine particles of soil 
• direction of the flow particle 

45.The activity of clay is defined as the ratio of ?

• liquid limit to plastic limit 
• liquidity index to plasticity index 
• plasticity index to clay fraction 
• plasticity index to shrinkage index 

46.A sample of clay and a sample of sand have the same specific gravity and void ratio. Their permeabilities will differ because ?

• their porosities will be different 
• their densities will be different 
• their degrees of saturation will be different 
• the size ranges of their voids will be different 

47.The coefficient of earth pressure at rest for stiff clay is about ?

• 0.4 
• 0.5 
• 0.6 
• 0.8 

48.The effective stress on the soil is due to the ?

• external load acting on the soil 
• weight of the soil particles 
• weight of water present in soil pores 
• both (a) and (b) 

49.The bearing capacity factors Nc, Nq, and N?, are functions of ?

• cohesion of the soil 
• friction angle 
• internal friction angle 
• both (a) and (b) 

50.The ratio of the volume of voids to the total volume of soil mass is called ?

• water content ratio 
• porosity 
• void ratio 
• degree of saturation

51.The submerged or buoyant unit weight of soil is equal to the ......... of unit weight of saturated soil and unit weight of water ?

• sum 
• difference 
• product 
• ratio 

52.The sensitivity of a normal clay is about ?

• 2 to 4 
• 4 to 8 
• 8 to 15 
• 15 to 20 

53.According to Indian standards, in a 2 mm sieve ?

• there are two holes 
• each sieve is circular and its diameter is 2 mm 
• each hole is a square and its side is 2 mm 
• there are two holes per cm length of the mesh 

54.Toughness index is the ratio of ?

• flow index and plasticity index 
• plasticity index and flow index 
• liquidity index and flow index 
• flow index and liquidity index 

55.The liquid limit minus plastic limit is termed as ?

• flow index 
• plasticity index 
• shrinkage index 
• liquidity index 

56.The coefficient of consolidation of a soil is affected by ?

• compressibility 
• permeability 
• both (a) and (b) 
• none of these 

57.The ratio of the liquid limit minus the natural content of a soil to its plasticity index, is known as ?

• toughness index 
• liquidity index 
• flow index 
• relative consistency 

58.When the consistency index is zero, then the soil is at its ?

• elastic limit 
• plastic limit 
• liquid limit 
• semi-solid state 

59.If the volume of voids is equal to the volume of soil solids, then the values of porosity and ratio are respectively ?

• 0 and 0.5 
• 0 and 1 
• 0.5 and 1 
• 1 and 0.5 

60.The useful method of finding the shear strength of very plastic cohesive soils is by means of ?

• cone test 
• penetration test 
• vane shear test 
• torsional shear test.