1. Choose the correct option from the following:

Water content of soil can

never be greater than 100%

take values only from to 100%

be less than

be greater than 100%

Valid range for the voids, is

0 n 100

0 n 100

n 0

n 0

When the plastic limit of a soil is greater than the liquid limit, then the plasticity index is reported as

negative

zero

non-plastic

1

Coarse grained soils are best compacted by a

drum roller

rubber tyred roller

sheep's foot roller

vibratory roller

If the shearing stress is zero on two planes, then the angle between the two planes is

45°

90°

135°

225°

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

cohesion only

angle of internal friction only

both cohesion and angle of internal friction

None of the above

Which of the following pairs is/are correctly matched?

Standard penetration test density -Relative

Vane shear Cohesion

Consolidation test Bearing capacity

B and C

A alone

A and B

Band C

Find the relation between w and Sr for a soil sample. Here, e Void ratio, G Specific gravity, w Water content, Sr =Saturation ratio.

Describe the Pycnometer method to determine water content for coarse gained soils with known specific gravity G.

3. Calculate the coefficient of permeability of a soil sample, 6 cm in height and 50 cm^2 in cross-sectional area, if a quantity of water equal to 430 ml is passed down in 10 minutes, under an effective constant head of 40 cm. On over-drying, the test specimen has a mass of 498 g. Taking the specific gravity of soil solids as 2.65, calculate the seepage velocity of water during the test.

Discuss the Mohr-Coulomb Failure theory in detail

A cylinder of soil fails under an axial vertical stress of 160 kN/m^2 when it is laterally unconfined. The failure plane makes an angle of 50° with the horizontal. Calculate the value of cohesion and the angle of internal friction of the soil.

Explain the Proctor Needle method to determine water content.

Write the factors which compacted density of soil. affect the

Write the assumptions in Terzaghi's analysis for bearing capacity of soil.

Design a strip footing to carry a load of 750 kN/m at a depth of 1.6 m in a c soil having a unit weight of 18 kN/m^3 and shear strength parameters as c =20 kN/m^3 and cj) Determine the width of footing, using a factor of safety of 3 against shear failure. Use Terzaghi's equations. For cj) Nc 25.1, Nq 12.7 and N.y =9·7.

7. Write short notes on any four of the following:

Augur Boring

Standard Penetration Test

Negative Skin Friction

Under-Reamed Pile Foundations

Spread Footing

Disturbed and Undisturbed Samples