1(a)
Describe standard penetration test as per IS:2131 guidelines. How to apply corrections to observed SPT - values?

10 M

1(b)
Estimate the grand water table, the following data. Depth upto which water is boiled out 18 meters. Water rise on 1

^{st}day = 0.95m, 11day = 0.86m and III day = 0.78m. Use Hvorselev's method.
10 M

2(a)
Explain equivalent point load method of determining σ

_{2}-at any point with in loaded area.
8 M

2(b)

Point loads 64kN, 15kN and 21kN, 1.5m apart in a straight line at the surface of soil mass. Calculate the resultant stress produced by these loads on a horizontal plane one meter below the surface at points vertically below the loads and also half way (mid point) between them. The vertical pressure σ _{2} du to point load Q is given by Boussinesq'a equation \( \sigma _{2}=\dfrac{Q}{z^{2}}1_{B} \) .

r/z | 0 | 0.75 | 1.5 | 2.25 | 3.0 |

I_{B} |
0.4775 | 0.1565 | 0.0251 | 0.053 | 0.0015 |

Sketch the curve showing distribution of these resultant stresses at that level.

12 M

3(a)
Explain with a neat sketch a method of locating the phreatic line in a homogeneous earth dam with horizontal filter.

10 M

3(b)
List the applications of flow net. Discuss about the validate of Darcy's law in determining quantity of seepage.

8 M

3(c)
An earthen dam is built on a impervious foundation with a horizontal filter under the downstrem slope. The horizontal and vertical permeability of the soil material in the dam are respectively 4 × 10

^{-5}and 1 ×10^{-5}m/sec. Full reservoir level is 20 meters above downstream filter. Flow net consists of 4 flow channels and 15 equipotential drops. Estimate seepage loss per meter length of the dam.
2 M

4(a)
Distinguish between Colulomb's earth pressure theory and Rankine's earth pressure theory.

4 M

4(b)
Describe Rebhann;s graphical method of finding active earth pressure on a retaining wall.

16 M

5(a)
Obtain an expression for factors against sliding in C-ϕ soil by the method of slices. Explain determination of factor of safety by method of slices method.

14 M

5(b)
An embankment is inclined at an angle 38° and its height is 20 meters. The angle of shearing resistance is 15° and the cohesion intercept is 50 kN/m

^{2}. The unit weight of soil is 16.5 kN/m^{3}. Find the factor o safety with respect with respect to cohesion. Consider Taylor's stability number = 0.08.
6 M

6(a)
List the assumptions of Terzaghi's bearing capacity equation.

8 M

6(b)
Calculate the ultimate bearing capacity of a 2 meter wide square footing resting on a ground surface of a sand deposit with the following properties: i) Unit weight is 18.6 kN/m

ii) Angle of internal friction = 38°. Also calculate ultimate bearing capacity of same footing when the footing is placed at depth of 1m below the ground surface. Take N

^{3};ii) Angle of internal friction = 38°. Also calculate ultimate bearing capacity of same footing when the footing is placed at depth of 1m below the ground surface. Take N

_{q}= 41.4, N_{r}=42.2 for ϕ =38°. Adopt Terzaghi's equation . Also calculate percentage increase in bearing capacity with increase in depth from surface to 1 meter from natural ground level.
12 M

7(a)
Discuss about the components of settlement.

8 M

7(b)
The soft normally consolidated clay layer is 18 meter thick. The natural water content is 45%. The saturated unit weight is 18kN/m

^{3}. The grain specific gravity is 2.70 and the liquid limit = 63%. The vertical stress increment at the centre of the layer due to the founcation load is 9kN/m^{2}. The ground water level is at the surface of the clay layer. Determine the consolidation settlement of the foundation.
12 M

8(a)
List and explain the classification of pile foundation base on function and material.

14 M

8(b)
Discuss about the factors governing minimum depth of foundation as per IS:1904 guidelines.

6 M

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