For a sheet pile with embedment D=10 ft, the average hydraulic gradient in the heave zone is iav=0.36. The soil has a saturated unit weight of 112 lb/ft3. What is the factor of safety against heaving? Use a unit weight of water of 62.4 lb/ft3.
Explanation
To solve this problem, you first calculate the submerged unit weight of the soil. Then, you use the provided average hydraulic gradient and the unit weight of water to find the uplift pressure gradient. The factor of safety is the ratio of the submerged unit weight to this uplift pressure gradient, as per Equation (9.15).
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