Principles of Geotechnical Engineering (MindTap Course List)
9th Edition
ISBN: 9781305970939
Author: Braja M. Das, Khaled Sobhan
Publisher: Cengage Learning
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Question
Chapter 15, Problem 15.20P
(a)
To determine
Find the undrained cohesion
(b)
To determine
Find the nature of the critical circle.
(c)
To determine
Find the distance that the surface of sliding intersects the bottom of the excavation.
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Compute the cohesion of the clay. The results of a three consolidated undrained tri-axial tests on a saturated clay are as follows : a. 10.45 kPab. 12.25 kPac. 11.62 kPad. 15.62 kPa
(Note:Depth of rock layer is 2m not 12 m.)
Q A cut slope was excavated in a saturated clay with a slope angle β = 57 ͦ with the horizontal. Slope failure occurred when the cut reached a depth of 8 m. Previous soil explorations showed that a rock layer was located at a depth of 2 m below the ground surface. Assuming an undrained condition and that ɣsat = 21 kN/m3 : Determine the undrained cohesion of the clay (Fig 3). What was the nature of the critical circle? With reference to the top of the slope, at what distance did the surface of the sliding intersect the bottom of the excavation?
3.25 In a site consisting entirely of clays, an electric friction cone
penetrometer measures the cone resistance q, at a depth of
8.0 m as 0.75 MN/m2. The water table is at 3.0 m below the
ground level. The unit weights of the clay above and below
the water table are 16.5 kN/m3 and 19.0 kN/m2, respectively.
Estimate the undrained shear strength, preconsolidation
pressure, and overconsolidation ratio at this depth.
Chapter 15 Solutions
Principles of Geotechnical Engineering (MindTap Course List)
Ch. 15 - Prob. 15.1PCh. 15 - Prob. 15.2PCh. 15 - Prob. 15.3PCh. 15 - Prob. 15.4PCh. 15 - Prob. 15.5PCh. 15 - Prob. 15.6PCh. 15 - Prob. 15.7PCh. 15 - Prob. 15.8PCh. 15 - Prob. 15.9PCh. 15 - Prob. 15.10P
Ch. 15 - Prob. 15.11PCh. 15 - Prob. 15.12PCh. 15 - Prob. 15.13PCh. 15 - Prob. 15.14PCh. 15 - Prob. 15.15PCh. 15 - Prob. 15.16PCh. 15 - Prob. 15.17PCh. 15 - Prob. 15.18PCh. 15 - Prob. 15.19PCh. 15 - Prob. 15.20PCh. 15 - Prob. 15.21PCh. 15 - Prob. 15.22PCh. 15 - Prob. 15.23PCh. 15 - Prob. 15.27PCh. 15 - Prob. 15.28PCh. 15 - Prob. 15.29PCh. 15 - Prob. 15.30PCh. 15 - Prob. 15.31PCh. 15 - Prob. 15.32P
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