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Abstract

The Phenomenon of wave-induced liquefaction has arrested increasing attention in recent years in considering the integrity of nearshore and offshore installations such as pipelines, anchors, platform structures and breakwaters.
There are two different mechanisms for wave- induced liquefaction, namely transient and residual liquefaction, depending on the way the excess pore pressure is generated. The former is generated by the transient or oscillatory nature of the excess pore pressure which occurs periodically during a storm responding to wave. The latter which is caused by the residual or progressive nature of the excess pore pressure occurs after a certain cycles of waves. This paper presents a procedure for analysis of wave-induced residual liquefaction. A model for generation of pore water pressure is used and effect of simultaneous dissipation is included in the analysis. In this model the shear stress is calculated for a seabed of finite thickness by use of an analytical approach. Then the governing equation for the generation and dissipation of pore water pressure is formulated and solved by a numerical method. This solution is validated with the analytical solution of the simplified cases and it is also compared with the undrained analysis. Then the effects of several pertinent wave and soil parameters on the liquefaction potential are examined in detail. This procedure is for free field conditions however it can be used as a first approximation in the presence of structures.