Geotechnical Engineering Set 6 MCQs

Q1 | The ratio of the difference between the void ratio of the soil in its loosest state and its natural void ratio (e) to the difference between the void ratios in the loosest and fully dense state, is generally termed as

Degree of density

Relativity

Density index

All the above

Q2 | For determining the ultimate bearing capacity of soil, the recommended size of a square bearing plate to be used in load plate test should be 30 to 75 cm square with a minimum thickness of

5 mm

10 mm

15 mm

25 mm

Q3 | Within the consolidation process of a saturated clay

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

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

Both neutral pressure and effective pressure decrease

Both neutral pressure and effective pressure increase

Q4 | An unsaturated 100 cm3 sample of soil weighs 190 g. If its dried weight is 160 g, watercontent of the soil, is

0.188

0.288

0.388

0.588

Q5 | Pick up the correct statement from the following:

If the ratio of depth to width is less than 2, it is shallow foundation

If the ratio of depth to width is more than 2, it is deep foundation

If the ratio of the length to width is between 1 and 2, it is spread foundation

All the above

Q6 | Pick up the correct statement from the following:

A maximum value of dry density is obtained at optimum water content

At low value of water content most soils tend to be stiff

At high water content, the dry density decreases with an increase of water content

All the above

Q7 | Select the correct statement.

Coefficient of compressibility of an over-consolidated clay is less than that of a normally consolidated clay

Coefficient of compressibility of an over-consolidated clay is greater than that of a normally consolidated clay

Coefficient of compressibility is constant for any clay

None of the above

Q8 | Pick up the correct statement from the following:

Isotropic consolidation of clay can be obtained in the triaxial apparatus under equal all-round pressure

If the present effective stress is the maximum to which the clay has ever been subjected, it is called normally consolidated clay

If the present effective stress in the past was more than present effective stress, it is called over-consolidated clay

All the above

Q9 | Compression of soil occurs rapidly if voids are filled with

Air

Water

Partly with air and partly with water

None of these

Q10 | For better strength and stability, the fine grained soils and coarse grained soils are compacted respectively as

Dry of OMC and wet of OMC

Wet of OMC and dry of OMC

Wet of OMC and wet of OMC

Dry of OMC and dry of OMC where OMC is optimum moisture content

Q11 | Chemical weathering of soil is caused due to

Oxidation

Carbonation

Hydration

All the above

Q12 | According to IS : 2720 - 1965, the composition of a dispersing solution used in pipette analysis for determining the size of particles, is

sodium-hexametaphosphate 33 g, sodium carbonate 7 g and distilled water one litre

sodium-hexametaphosphate 7 g, sodium carbonate 33 g and distilled water one litre

sodium-hexametaphosphate 23 g, sodium carbonate 17 g and distilled water one litre

None of these

Q13 | The minimum depth of building foundations on

Sandy soils is 80 cm to 100 cm

Clay soils is 90 cm to 160 cm

Rocky soils is 5 cm to 50 cm

All the above

Q14 | The effect of cohesion on a soil is to

Reduce both the active earth pressure intensity and passive earth pressure intensity

Increase both the active earth pressure intensity and passive earth pressure intensity

Reduce the active earth pressure intensity but to increase the passive earth pressure intensity

Increase the active earth pressure intensity but to reduce the passive earth pressure intensity

Q15 | If voids ratio is 0.67, water content is 0.188 and specific gravity is 2.68, the degree ofsaturation of the soil, is

25%

40%

60%

75%

Q16 | Pick up the incorrect statement from the following:

The smaller the size of the pores, the higher the water can rise above the water table

Below the water table, the pore water may be static

The hydrostatic pressure depends on the depth below the water level

None of these

Q17 | A soil mass coated with a thin layer of paraffin weighs 460 g. When immersed, it displaces 299 cc of water. The weight of paraffin is 10 g. If specific gravity of solids is 2.5 and that of paraffin 0.9, the void ratio of soil, is

0.55

0.6

0.65

0.7

Q18 | Select the incorrect statement.

Bearing capacity of a soil depends upon the amount and direction of load

Bearing capacity of a soil depends on the type of soil

Bearing capacity of a soil depends upon shape and size of footing

Bearing capacity of a soil is independent of rate of loading

Q19 | Over-consolidation of soils is caused due to

Erosion of over burden

Melting of ice sheets after glaciations

Permanent rise of water table

All the above

Q20 | The consistency index of a soil is defined as the ratio of

Liquid limit plus the natural water content to the plasticity index of the soil

Liquid limit minus the natural water content to the plasticity index of the soil

Natural water content of a soil minus plastic limit to the plasticity index of the soil

Natural water content of a soil plus its plastic limit to the plasticity index of the soil

Q21 | Which of the following types of soil is transported by gravitational forces?

Loess

Talus

Drift

Dune sand

Q22 | Soil classification of composite soils, exclusively based on the particle size distribution, is known

Particle classification

Textural classification

High Way Research Board classification

Unified soil classification

Q23 | When the degree of saturation is zero, the soil mass under consideration represents

One phase system

Two phase system with soil and air

Two phase system with soil and water

Three phase system

Q24 | Pick up the cohesive soil from the following:

Red earth

Clay

Black cotton soil

Compacted ground

Q25 | For proper field control, which of the following methods is best suited for quick determination of water content of a soil mass?

Oven drying method

Sand bath method

Alcohol method

Calcium carbide method