A compacted earth fill is constructed on a soft, saturated clay (figure below). The fill was compacted to an average dry unit weight of 19 kN/m³ and water content of 15%. The shearing strength of the fill was determined by CU tests on samples compacted to representative field conditions. The shear strength parameters are Su = 45 kPa, 4, = 34°, and s = 28°. The variation of undrained shear strength of the soft clay with depth as determined by simple shear tests is shown in the figure below, and the friction angle at the critical state is 4es = 30°. The average water content of the soft clay is 40%. Compute the factor of safety using Bishop's simplified method. Assume that a tension crack will develop in the fill. 8 m 10 m 6 m Clay crust Su (kPa) 7.5 15 Compacted fill E 1.0 2.5 4 m Soft clay 5.0 Very dense sand 10 kPa [Budhu M. Soil Mechanics & Foundations (3E), p. 720] Page I of 2 Depth (m)

A compacted earth fill is constructed on a soft, saturated clay (figure below). The fill was compacted to an average dry unit weight of 19 kN/m³ and water content of 15%. The shearing strength of the fill was determined by CU tests on samples compacted to representative field conditions. The shear strength parameters are Su = 45 kPa, 4, = 34°, and s = 28°. The variation of undrained shear strength of the soft clay with depth as determined by simple shear tests is shown in the figure below, and the friction angle at the critical state is 4es = 30°. The average water content of the soft clay is 40%. Compute the factor of safety using Bishop's simplified method. Assume that a tension crack will develop in the fill. 8 m 10 m 6 m Clay crust Su (kPa) 7.5 15 Compacted fill E 1.0 2.5 4 m Soft clay 5.0 Very dense sand 10 kPa [Budhu M. Soil Mechanics & Foundations (3E), p. 720] Page I of 2 Depth (m)

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 9.14P

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