Find the vertical stress increase at 4 m below A, B, and C.
Answer to Problem 8.27CTP
The increase in the vertical stress
The increase in the vertical stress
The increase in the vertical stress
Explanation of Solution
Given information:
The depth of the point from the ground level,
The intensity of the uniform pressure,
Calculation:
Vertical stress increase at point A:
Show the free-body diagram of the L-shaped raft as in Figure 1.
Rectangle 1:
Find the value of
Substitute 4 m for
Find the value of
Substitute 6 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 2:
Find the value of
Substitute 8 m for
Find the value of
Substitute 6 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 3:
Find the value of
Substitute 8 m for
Find the value of
Substitute 8 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Find the increase in vertical stress
Substitute
Therefore, the increase in the vertical stress
The vertical stress increase at point B:
Show the free-body diagram of the L-shaped raft as in Figure 2.
Rectangle 1:
Find the value of
Substitute 12 m for
Find the value of
Substitute 6 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 2:
Find the value of
Substitute 8 m for
Find the value of
Substitute 14 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 3:
Find the value of
Substitute 8 m for
Find the value of
Substitute 6 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Find the increase in vertical stress
Substitute
Therefore, the increase in the vertical stress
The vertical stress increase at point C:
Show the free-body diagram of the L-shaped raft as in Figure 3.
Rectangle 1:
Find the value of
Substitute 12 m for
Find the value of
Substitute 14 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 2:
Find the value of
Substitute 12 m for
Find the value of
Substitute 8 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Rectangle 3:
Find the value of
Substitute 8 m for
Find the value of
Substitute 8 m for
Refer Figure 8.16 “Variation of
For
The value of variation
Find the increase in vertical stress
Substitute
Find the increase in vertical stress
Substitute
Therefore, the increase in the vertical stress
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Chapter 8 Solutions
Fundamentals of Geotechnical Engineering (MindTap Course List)
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