ABSTRACT
A CPT-based procedure to estimate the severity of liquefaction ejecta is presented. It employs a liquefaction ejecta demand parameter (LD ) that captures the amount of upward seepage pressure that can produce artesian flow due to elevated excess hydraulic head and a crust layer resistance parameter (CR ) that captures the strength and thickness of the nonliquefiable crust layer. LD tends to increase systematically as ejecta severity increases at the thick, clean sand sites, and low LD values are estimated at stratified soil sites that did not produce ejecta. CR captures the differing performances of sites with and without a competent crust layer overlying a thick liquefiable layer with a high LD value. The proposed LD – CR liquefaction ejecta severity chart separates cases with severe or extreme ejecta, which have high LD and low CR values, from cases with minor or no ejecta, which have low LD and high CR values.
