Concept explainers
(a)
Find the normal and shear stress on a plane inclined at
(a)
Answer to Problem 12.17P
The normal stress on a plane inclined at
The shear stress on a plane inclined at
Explanation of Solution
Given information:
Specimen I:
The chamber pressure
The deviator stress is
The inclined angle with major principal plane
Specimen II.
The chamber pressure
The deviator stress
Calculation:
For specimen I:
Find the major principal effective stress at failure
Substitute
Find the normal stress
specimen I using the equation.
Here,
Substitute
Thus, the normal stress on a plane inclined at
Find the shear stress
specimen I using the equation.
Substitute
Thus, the shear stress on a plane inclined at
(b)
Find the normal and shear stress on the failure plane at failure for specimen II.
(b)
Answer to Problem 12.17P
The normal stress on the failure plane at failure for specimen II is
The shear stress on the failure plane at failure for specimen II is
Explanation of Solution
Calculation:
Show the Mohr-Coulomb failure expression to find the major effective principal stress for specimen I as shown below:
Here,
Substitute
Substitute
Express the Mohr-Coulomb failure for specimen II using Equation (5).
Substitute
Subtract the Equation (6) from (7).
Calculate the angle of inclination on the failure plane using the equation:
Substitute
Find the major principal effective stress at failure
Substitute
Find the normal stress
Substitute
Thus, the normal stress on the failure plane at failure
Find the shear stress
Substitute
Thus, the shear stress on the failure plane at failure
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Chapter 12 Solutions
Bundle: Principles Of Geotechnical Engineering, Loose-leaf Version, 9th + Mindtap Engineering, 2 Terms (12 Months) Printed Access Card
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