A 20 m long concrete pile is shown in Figure P12.2. Estimate the ultimate point load Qp by
- a. Meyerhof’s method
- b. Vesic’s method
- c. Coyle and Castello’s method
Use m = 600 in Eq. (12.28).
a.
Find the ultimate point load using Meyerhof’s method.
Answer to Problem 9.1P
The ultimate point load using Meyerhof’s method is
Explanation of Solution
Given information:
The length of the concrete pile is 20 m.
Area of the concrete pile
Soil friction angle
Unit weight of sand
Depth
Calculation:
Find the bearing capacity
Substitute 20 m for D and
Refer Table 12.6. “Interpolated values of
The value of
Take the atmospheric pressure
Find the value of ultimate point load
Here,
Find the value of
Substitute
Find the value of
Substitute
Substitute
The ultimate load should satisfy,
Substitute
So take the value of
Therefore, the ultimate point load using Meyerhof’s method is
b.
Find the ultimate point load using Vesic’s method.
Answer to Problem 9.1P
The ultimate point load using Vesic’s method is
Explanation of Solution
Calculation:
Find the modulus of elasticity
Substitute 600 for m and
Find the Poisson’s ratio of the soil using the relation:
Substitute 42 for
Find the value of average volumetric strain in the plastic zone below the pile point
Substitute 42 for
Find the value of rigidity index
Substitute
Find the value of reduced rigidity index
Substitute 66.1 for
Find the mean effective normal ground stress
Substitute
Refer Table 12.8. “Bearing capacity factors
The value of
Find the value of ultimate point load
Substitute
Therefore, the ultimate point load using Vesic’s method is
c.
Find the ultimate point load using Coyle and Castello’s method.
Answer to Problem 9.1P
The ultimate point load using Coyle and Castello’s is
Explanation of Solution
Calculation:
Find the value of
Substitute 20 m for L and 460 mm for D.
Refer Figure 12.20, “Variation of
The value of
Find the value of ultimate point load
Substitute
Therefore, the ultimate point load using Coyle and Castello’s method is
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Chapter 9 Solutions
Principles of Foundation Engineering (MindTap Course List)
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