9411018 Figueroa The recent Northridge earthquake in Los Angeles, CA generated extensive damage to buildings, roadway, bridges, and other civil engineering works and structures. News reports and communications from researchers indicated the evidence of liquefaction at several locations. Researchers have attempted to determine the parameters which could better define the liquefaction potential of a soil deposit and handle random loading during the past two decades. Seed and Idriss among others, proposed a general method for evaluating the liquefaction potential of a soil deposit using various parameters representative of the deposit, and the magnitude of the expected earthquake and the shear stresses induced by the design earthquake. More recently, Figueroa, Saada et al. in a project funded by NSF, established a relationship between the unit energy imparted to the soil up to liquefaction and the effective confining pressure, relative density and shear strain amplitude for a sand. These findings set the basis for the development of a new method for evaluating the liquefaction potential of a soil deposit using the unit energy approach. Liquefaction observed during the Northridge earthquake offers the great opportunity to initiate the validation of this new method of liquefaction potential evaluation through the torsional shear testing of soils representative of locations which experienced this phenomenon, and the analysis of earthquake records. ***
