2020 Volume 76 Issue 2 Pages I_462-I_467
This paper assessed the possibility of wave-induced liquefaction in seabed near Japan coast using Ocean Wave Information (NOWPHAS). Liquefaction potential at each observation point was assessed based on the comparison of the cyclic stress ratio, which expresses the severity of waves on the seabed, and the critical cyclic stress ratio below which liquefaction does not occur under progressive waves. Theoretical analysis considering cyclic plasticity of sand was validated against centrifuge wave tank tests under irregular waves and then applied to a risk assessment of the field. It was found that severe waves whose cyclic stress ratio exceed the liquefaction resistance in the loosely deposited seabed of sand have occasionally attacked Japanese coast. The analytical results showed that the excess pore water pressures developed and dissipated as the wave height increased and decreased, and continuous severe waves brought about liquefaction.
