(a)
Find the drained angle of friction for the silty clay soil.
(a)
Answer to Problem 12.4P
The drained angle of friction for the silty clay soil is
Explanation of Solution
Given information:
The diameter (d) of clay sample is 63.5 mm.
The height (h) of the clay sample is 32 mm.
Calculation:
Calculate the area of specimen (A) as follows:
Substitute 63.5 mm for d.
Find the normal stress
Here, N is the normal force and A is the area of specimen.
Substitute
Similarly calculate the normal stress
Test no | Normal force, N(N) | Normal stress |
1 | 84 | 26.58 |
2 | 168 | 53.16 |
3 | 254 | 80.38 |
4 | 360 | 113.92 |
Table 1
Find the shear strength
Substitute
Find the angle of friction
Substitute
Similarly calculate the angle of friction
Test no | Shear force, S (N) | Shear strength, | Angle of friction |
1 | 28.9 | 9.14 | 18.97 |
2 | 59.6 | 18.86 | 19.53 |
3 | 89.1 | 28.19 | 19.33 |
4 | 125.3 | 39.65 | 19.19 |
Table 2
Calculate the drained angle of friction
The average value of angle of friction of all tests is the drained angle of friction.
Refer to the Table 2,
Find the drained angle of friction as follows:
Thus, the drained angle of friction for the silty clay soil is
(b)
Find the shear strength of the clay in the field at location A.
(b)
Answer to Problem 12.4P
The shear strength of the clay in the field at location A is
Explanation of Solution
Given information:
The specific gravity
The specific gravity
The unit weight
The void ratio (e) is 0.72.
The water content (w) of silty clay is
The depth
The depth
The depth
Calculation:
Calculate the dry unit weight
Substitute 2.69 for
Calculate the saturated unit weight
Substitute 0.72 for e,
Calculate the saturated unit weight
Substitute
Determine the normal stress
Substitute
Find the shear strength
Here,
Substitute
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Chapter 12 Solutions
Principles of Geotechnical Engineering (MindTap Course List)
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