Definition of Terms Related to Liquefaction

Important variations, discrepancies, and ambiguities have developed in terminology used to describe the liquefaction phenomenon and its effects. In an attempt to rectify this problem and bring unity and consistency in usage, the Geotechnical Division's Committee on Soil Dynamics suggested a list of recommended definitions, which include: liquefaction, cyclic strain softening, pore pressure ratio, peak pore pressure ratio, 100% pore pressure ratio, shear strength, cyclic shear resistance, normal strain, shear strain, peak strain, peak to peak strain, limited flow strain, unlimited flow strain, ground failure, lateral spreading, flow failure, and sand boil. It is recognized that many engineers have strong opinions concerning definitions and terminology. Therefore, the Committee on Soil Dynamics encourages written discussion concerning the use and implementation of these suggested terms and definitions. It is hoped that this document and the ensuing discussions will ultimately lead to an adoption of terms and definitions that will be used consistently in geotechnical practice and reports.