Design Problems in Soil Liquefaction

Abstract

An attempt is made to clarify some aspects of the problems encountered in evaluating the stability of embankments under conditions where a potential for soil liquefaction exists. It is suggested that at the present time, the most prudent method of minimizing the hazards associated with liquefaction‐induced sliding and deformations is to plan new construction or devise remedial measures in such a way that either high pore water pressures cannot build up in the potentially liquefiable soil, and thus liquefaction cannot be triggered, or, alternatively, to confine the liquefiable soils by means of stable zones, so that no significant deformations can occur; by this means, the difficult problems associated with evaluating the consequences of liquefaction (sliding or deformations) are avoided. However, when large deformations can possibly be tolerated, it may be adequate and economically advantageous to simply ensure the stability of the embankment against major sliding after liquefaction has occurred. Evaluating this possibility requires a knowledge of the residual strength of the liquefied soil, and, while laboratory test procedures have been developed for determining such a strength, it is suggested that the establishment of a relationship between this property of a soil, as determined by field performance studies, and some in situ soil characteristic, such as penetration resistance, may provide the most practical method for evaluating residual strengths in cases where such values are required. Available data based on case studies is summarized and plotted in chart form for this purpose.