A 5-m depth of sand overlies a 6-m thick layer of clay, the water table being at the surface; the permeability of the clay is very low. The saturated unit weight of the sand is 19 kN/m3 and that of clay is 20 kN/m3. A 4-m depth of fill material of unit weight 20 kN/m3 is placed on the surface over an extensive area. Determine the effective vertical stress at the centre of the clay layer a. immediately after the fill has been placed, assuming this to take place rapidly, and b. many years after the fill has been placed. Fill WT Sand m 5 Clay 8. 11

A 5-m depth of sand overlies a 6-m thick layer of clay, the water table being at the surface; the permeability of the clay is very low. The saturated unit weight of the sand is 19 kN/m3 and that of clay is 20 kN/m3. A 4-m depth of fill material of unit weight 20 kN/m3 is placed on the surface over an extensive area. Determine the effective vertical stress at the centre of the clay layer a. immediately after the fill has been placed, assuming this to take place rapidly, and b. many years after the fill has been placed. Fill WT Sand m 5 Clay 8. 11

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter9: Consolidation

Section: Chapter Questions

Problem 9.8P

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