Concept explainers
(a)
Find the undrained cohesion of the clay using Bjerrum’s
(a)
Answer to Problem 12.10P
The undrained cohesion of the clay using Bjerrum’s
Explanation of Solution
Given information:
The height of the vane (h) is 127 mm.
The width of the vane (d) is 63.5 mm.
The torque (T) is
The liquid limit (LL) is 50.
The plastic limit (PL) is 18.
Calculation:
Find the ratio of height (h) to diameter (d):
Substitute 127 mm for h and 63.5 mm for d.
Find the value of K using the formula.
Substitute 63.5 mm for d.
Find undrained shear strength
Substitute
Find the plasticity index (PI) using the relation:
Substitute 50 for LL and 18 for PL.
Find the correction factor
Substitute 32 for PI.
Find the corrected undrained shear strength
Substitute
Thus, the undrained cohesion of the clay by Bjerrum’s
(b)
Find the undrained cohesion of the clay using Morris and Williams’
(b)
Answer to Problem 12.10P
The undrained cohesion of the clay using Morris and Williams’
Explanation of Solution
Refer to part (a);
The value of PI is 32.
Find the correction factor using the formula:
Substitute 32 for PI.
Find the corrected undrained shear strength
Refer part (a), the undrained shear strength
Substitute
Thus, the undrained cohesion of the clay by Morris and Williams’
(c)
Find the undrained cohesion of the clay using Morris and Williams’
(c)
Answer to Problem 12.10P
The undrained cohesion of the clay using Morris and Williams’
Explanation of Solution
Given information:
The liquid limit (LL) is 50.
Calculation:
Find the correction factor using the formula:
Substitute 50 for LL.
Find the corrected undrained shear strength
Refer part (a), the undrained shear strength
Substitute
Thus, the undrained cohesion of the clay by Morris and Williams’
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Chapter 12 Solutions
Fundamentals of Geotechnical Engineering (MindTap Course List)
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