Dynamic failures of subsoils observed in waterfront areas

Abstract

Liquefaction and related phenomenon that occurred during the 1995 Kobe earthquake are discussed. The field investigation showed that the sites where liquefaction occurred are located in the area of recent reclamation near the sea. Although liquefaction occurred significantly in the harbor, there is no evidence of liquefaction near the quay walls which failed. It was also demonstrated that surface motion records can be used to estimate the thickness of liquefied subsoil. Shaking table tests were conducted on quay wall models to demonstrate a limited development of excess pore water pressure behind a wall. It seems that the large displacement of walls in Kobe Harbor can occur without liquefaction when the intensity of seismic inertia force is as strong as that which was experienced in 1995.