A layer of clay 4m thick lies between two layers of sand each 4m thick, the top of the upper layer of sand being ground level. The water table is 2 m below ground level but the lower layer of sand is under artesian pressure, the piezo- metric surface being 4m above ground level. The saturated unit weight of the clay is 20 kN/m and that of the sand 19KN/m'; above the water table the unit weight of the sand is 16.5 kN/m³. Calculate the effective vertical stresses at the top and bottom of the clay layer.

A layer of clay 4m thick lies between two layers of sand each 4m thick, the top of the upper layer of sand being ground level. The water table is 2 m below ground level but the lower layer of sand is under artesian pressure, the piezo- metric surface being 4m above ground level. The saturated unit weight of the clay is 20 kN/m and that of the sand 19KN/m'; above the water table the unit weight of the sand is 16.5 kN/m³. Calculate the effective vertical stresses at the top and bottom of the clay layer.

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter2: Geotechnical Properties Of Soil

Section: Chapter Questions

Problem 2.15P

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