Concept explainers
Refer to Figure 18.9. A cantilever sheet pile is driven into a granular soil where the water table is 2 m (L1) below the top of the sand. The properties of the sand are
Find the required actual depth of the sheet pile.
Answer to Problem 18.1P
The required actual depth of the sheet pile is
Explanation of Solution
Given information:
The depth of water level below the sand
The angle of internal friction for sand
The unit weight of the sand
The saturated unit weight of the sand
The depth below the ground level (L) is 6 m.
Calculation:
Show the cross section of cantilever sheet pile with dimensions as in Figure (1).
Refer Figure (1),
Find the depth of water table level
Find the rankine active pressure coefficient
Find the rankine passive pressure coefficient
Find the difference between the rankine active pressure coefficient and rankine passive pressure coefficient:
Find the effective unit weight of sand
At the water table level:
Find the intensity of the active pressure to the right of the pile
At the excavation level:
Find the intensity of the active pressure to the right of the pile
Find the depth below the dredge line
Find the area of the pressure diagram (P):
Find the area of the pressure diagram into center of pressure
Find the center of pressure to the area
Find the intensity of the passive pressure
Find the area
Find the area
Find the area
Find the area
Find the depth below point E
Use trial and error method to calculate depth below point E
Try
Substitute 4.30 m for
Hence, the assumption is correct.
The depth below point E is 4.30 m.
Find the depth below the dredge line to bottom of the pile (D):
Increase the depth below the dredge line to bottom of the pile by 30%. The depth below the dredge line to bottom of the pile (D) is 6.214 m.
Find required actual depth of the sheet pile
Thus, the required actual depth of the sheet pile is
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Chapter 18 Solutions
Principles of Foundation Engineering (MindTap Course List)
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