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FS L > 1.4: Excess pore pressure generation is considered negligible and the soil does not
experience an appreciable reduction in shear strength (CDMG 1997). In this case, the
drained shear strength is computed using the standard Mohr-Coulomb strength equation.
1.0 < FS L < 1.4: Partial excess pore pressure generation will have an effect on soil
strength and should be addressed. The magnitude of the pore pressure generation is a
function of FS L and soil type (Marcuson et al. 1990).
FS L < 1.0: Soils are expected to experience full pore pressure generation and residual
undrained shear strengths should be applied (Stark et al. 1997).
The latter two cases involving the generation of significant excess pore pressures are particularly
relevant and are discussed in the following sections.
4.2.1 Partial Excess Pore Pressure Generation (1.0 < FS L