Soil Stabilization And Soil Exploration Practice Questions

No. of blows for each 150 mm penetration 8, 6 and 9. We will not consider first 150 mm number of blows. Hence, for last 300 mm, number of blows are 15. Hence, observed SPT number = 15.

P: True In the Oedometer test, stress is applied to the soil specimen along the vertical axis, while strain in the horizontal direction is prevented by the confining ring (a condition of zero lateral strain). Thus it simulates at-rest condition. Q: True For a perfectly rigid footing resting on surface of sand deposit, the contact pressure distribution is zero at the edges and maximum at centre. However, for a very deep rigid footing on sand, the contact pressure distribution may tend to become like that of rigid footing on clayey soil, with edge contact stress greater than at its centre. R: True For cohesive soil, there is no need for overburden pressure correction (Peck et al 1974). For cohesionless soil at first overburden pressure correction is made, then if it is fine sand or silt under water table with N-value $\gt$ 15, dilatancy correction is made.

As thickness of sampler increase, disturbance increase

Currently no explanation available

Area ratio should be less than 10 % for a undisturbed sample. But in case of collecting a sample using split spoon sampler the area ratio is as high as 30%. So it is impossible to get a undisturbed sample with the help of a split spoon sampler. Also, the clearance ratio should be from 1 to 3 per cent.

Currently no explanation available