| Liquefaction-induced deformation of saturated granular soils is a major source of damage to soil structures, buried lifeline facilities, foundations, canals and roads. Liquefaction can occur in saturated loose to medium dense sands when subjected to rapid cyclic or monotonic loading. Finite element techniques using the concepts of steady state strength and collapse surface are employed here to perform deformation analyses of liquefaction.;Post-earthquake deformation analysis of the Upper San Fernando Dam, San Fernando Valley, California, which suffered large deformations as a result of the 1971 San Fernando earthquake, is carried out. Deformations comparable with the deformations observed shortly after the earthquake are obtained.;A literature review on earthquake-induced lateral spreading of gently sloping granular deposits is performed. Based on the information provided from the literature, it is suggested that large deformations in lateral spreading are triggered by gravity. The notion is reinforced by the observation of delayed response. According to this phenomenon, response of saturated soil structures to earthquakes continue long after the earthquake. A simplified numerical model, based on the method of post-earthquake deformation analysis, is suggested for analysis of lateral spreads.;The problem of static liquefaction is studied by numerical modeling and analyses of three centrifuge model tests and a full-scale field event. The liquefiable material in the centrifuge tests and the field event was Syncrude sand from Syncrude, Canada. The analyses indicated that the finite element model is capable of capturing the liquefaction-induced failure mechanics and pore pressure response of the sand. |
