(a)
Find the maximum shear stress developed within the soil.
(a)
Answer to Problem 13.27CTP
The maximum shear stress developed within the soil is
Explanation of Solution
Given information:
The depth (H) of slope is 5 m.
The angle
The unit weight of the soil
The cohesion
The angle
Calculation:
The maximum shear stress developed at soil rock interface (5 m depth).
Find the maximum shear stress
Substitute
Thus, the maximum shear stress developed within the soil is
(b)
Find the maximum shear strength available within the soil.
(b)
Answer to Problem 13.27CTP
The maximum shear strength available within the soil is
Explanation of Solution
Given information:
The depth (H) of slope is 5 m.
The angle
The unit weight of the soil
The cohesion
The angle
Calculation:
Find the maximum shear strength
Substitute
Thus, the maximum shear strength available within the soil is
(c)
Find the factor of safety of the slope.
(c)
Answer to Problem 13.27CTP
The factor of safety of the slope is
Explanation of Solution
Given information:
The depth (H) of slope is 5 m.
The angle
The unit weight of the soil
The cohesion
The angle
Calculation:
Find the factor of safety
Substitute
Therefore, the factor of safety of the slope is
(d)
Find the maximum possible depth for the soil before it becomes unstable.
(d)
Answer to Problem 13.27CTP
The maximum possible depth for the soil before it becomes unstable is
Explanation of Solution
Given information:
The depth (H) of slope is 5 m.
The angle
The unit weight of the soil
The cohesion
The angle
Calculation:
The slope becomes unstable then the factor of safety
Find the maximum possible depth
Substitute
Thus, the maximum possible depth for the soil before it becomes unstable is
(e)
Find the factor of safety with respect to cohesion when the friction is fully mobilized.
(e)
Answer to Problem 13.27CTP
The factor of safety with respect to cohesion when the friction is fully mobilized is
Explanation of Solution
Given information:
The depth (H) of slope is 5 m.
The angle
The unit weight of the soil
The cohesion
The angle
Calculation:
The developed angle of friction is equal to the angle of friction when the friction is fully mobilized. Therefore,
Find the developed cohesion in the soil using the equation:
Substitute
Substitute
Find the factor of safety
Substitute
Thus, the factor of safety with respect to cohesion when the friction is fully mobilized is
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Chapter 13 Solutions
Fundamentals of Geotechnical Engineering (MindTap Course List)
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