2. The following laboratory data are available on the drained shear strength of a highly overconsolidated stiff clay at an effective normal stress range near 100 kPa: peak strength, c' = 10 kPa, o' 21°; residual strength, c' = 0, 4; = 12°. Factor of safety for slope stability analysis is defined as F.S. = (mobilized shear strength)/(shear stress). For one segment of a slip surface in a slope, the effective normal stress is 100 kPa and the factor of safety (for the segment) with respect to peak strength is 1.7. For the same segment compute: (a) F.S. with respect to the fully softened strength; (b) F.S. with respect to residual strength; (c) if the F.S. of the segment in part (b) also represented the F.S. of the whole slope, would you consider the slope to be stable or unstable?; (d) describe a method that could be used to improve the stability of the slope without making any excavations. = 22°; fully softened strength, c' 0, 4'

2. The following laboratory data are available on the drained shear strength of a highly overconsolidated stiff clay at an effective normal stress range near 100 kPa: peak strength, c' = 10 kPa, o' 21°; residual strength, c' = 0, 4; = 12°. Factor of safety for slope stability analysis is defined as F.S. = (mobilized shear strength)/(shear stress). For one segment of a slip surface in a slope, the effective normal stress is 100 kPa and the factor of safety (for the segment) with respect to peak strength is 1.7. For the same segment compute: (a) F.S. with respect to the fully softened strength; (b) F.S. with respect to residual strength; (c) if the F.S. of the segment in part (b) also represented the F.S. of the whole slope, would you consider the slope to be stable or unstable?; (d) describe a method that could be used to improve the stability of the slope without making any excavations. = 22°; fully softened strength, c' 0, 4'

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter12: Shear Strength Of Soil

Section: Chapter Questions

Problem 12.23P

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