A saturated compressible clay layer of thickness h is sandwiched between two sand layers, as shown in the figure. Initially, the total vertical stress and pore water pressure at point P, which is located at the mid-depth of the clay layer, were 150 kPa and 25 kPa, respectively. Construction of a building caused an additional total vertical stress of 100 kPa at P. When the vertical effective stress at P is 175 kPa, the percentage of consolidation in the clay layer at P Is

A saturated compressible clay layer of thickness h is sandwiched between two sand layers, as shown in the figure. Initially, the total vertical stress and pore water pressure at point P, which is located at the mid-depth of the clay layer, were 150 kPa and 25 kPa, respectively. Construction of a building caused an additional total vertical stress of 100 kPa at P. When the vertical effective stress at P is 175 kPa, the percentage of consolidation in the clay layer at P Is

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter9: In Situ Stresses

Section: Chapter Questions

Problem 9.12P

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Problem 1 A ground profile consists of 2 m of silty sand underlain by 3 m of clay. The ground water table is 3 m below the ground surface. The sand has a unit weight of 14 kN/m3. The clay has unit weight of 16 kN/m3 above the water table and 20 kN/m3 below the water table. a. Determine the total stress at bottom of the clay b. Determine the pore water pressure at the bottom of the clay c. Determine the effective stress at the bottom of the clay Problem 2 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 vertical effective pressure at the midheight of the clay layer before lowering of the water table in psf? b. What is the vertical effective pressure at the…