Parametric study of breaking solitary wave induced liquefaction of coastal sandyslopes

Abstract

Wave-induced soil liquefaction can cause serious damages to coastlines and coastal infrastructures. Although liquefaction caused by regular waves over flat sea beds has been extensively investigated, studies of tsunami-induced liquefaction of coastal sandy slopes have been relatively rare. In this work, parametric studies are conducted to investigate the liquefaction potential of coastal sandy slopes caused by breaking solitary waves. The dependence of the maximum liquefaction depth on soil permeability is studied at different cross-shore locations and for different offshore wave heights. The results suggest that tsunami can induce liquefaction failure of coastal sand slopes, and that the soil responses can be characterized by the ratio of the pore pressure diffusion time scale to the wave loading time scale. Under the same wave loading condition, an offshore soil column may experience the largest liquefaction depth, while the longest duration of liquefaction (which may physically correlate to the largest liquefaction volume) occurs in the seepage zone, because of the wave loading and unloading pattern above the seepagezone.