50 ft thick sand is underlain by 25 ft clay. The ground water table, initially at the ground surface, was lowered to a depth of 25 ft below the ground. After such lowering, the degree of saturation of the sand above water table was lowered to 20%. Saturated and dry unit weight of sand are 135 pcf and 116 pcf respectively. The saturated unit weight of clay is 120 pcf. a. what is the unit weight of the sand above the water table after lowering in pcf? b. What is the vertical effective pressure at the midheight of the clay layer when the water table is lowered 50 ft. Below the ground in psf?

50 ft thick sand is underlain by 25 ft clay. The ground water table, initially at the ground surface, was lowered to a depth of 25 ft below the ground. After such lowering, the degree of saturation of the sand above water table was lowered to 20%. Saturated and dry unit weight of sand are 135 pcf and 116 pcf respectively. The saturated unit weight of clay is 120 pcf. a. what is the unit weight of the sand above the water table after lowering in pcf? b. What is the vertical effective pressure at the midheight of the clay layer when the water table is lowered 50 ft. Below the ground in psf?

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter11: Compressibility Of Soil

Section: Chapter Questions

Problem 11.10P

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