Liquefaction Evaluation Procedure

A procedure for evaluating liquefaction susceptibility of a soil mass subjected to shear stress, such as in slopes, embankments, and foundations of structures, is presented. Liquefaction analysis is a stability analysis for which the shear strength in the numerator of the factor of safety equation is the undrained steady‐state strength, and the denominator is the driving shear stress. The driving shear stress is the shear stress required to maintain static equilibrium. The undrained steady‐state shear strength is a function only of the void ratio. Thus, one critical step of the procedure for liquefaction evaluation is the determination of the in‐situ void ratio and the correction of laboratory‐measured undrained steady‐state strength to account for unavoidable changes in void ratio of the soil during sampling and testing. Dilative soils are not susceptible to liquefaction. Cyclic load tests are not required to evaluate the susceptibility to liquefaction.