A 5m thick clay layer lies between two layers of sand each 4m thick, the top upper layer being at ground level. The water table is 2m below the ground level but the lower layer of sand is under artesian pressure, the piezometric head being 4m above ground level. The saturated density of clay is 20kN/m3 and that of sand is 19kN/m3 . Above the water table, unit weight of sand is 16.5kN/m3 . Calculate the effective vertical stress at the top and bottom of the clay layer.

A 5m thick clay layer lies between two layers of sand each 4m thick, the top upper layer being at ground level. The water table is 2m below the ground level but the lower layer of sand is under artesian pressure, the piezometric head being 4m above ground level. The saturated density of clay is 20kN/m3 and that of sand is 19kN/m3 . Above the water table, unit weight of sand is 16.5kN/m3 . Calculate the effective vertical stress at the top and bottom of the clay layer.

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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