Analysis of cases of gravity quaywall movement during earthquakes Available to Purchase

Earthquakes have damaged harbour structures, both recently and historically. Vivid examples are provided by two recent events: the Kobe earthquake (M_l = 7·2, 1995), involving Kobe port, Port Island, Rokko Island and Fukae Island in Japan; and the Chi-Chi earthquake (M_l = 7·3, 1999), involving Taichung Harbour in Taiwan. The results of surveys of deformation patterns of the ground surface at the two harbours after the events, and the published results of well-planned shaking-table tests, are analysed: the shaking-table tests provided images of the deformed profiles for the submerged backfill of a scaled-down quaywall model. On the basis of these data a simple model is proposed to explain the failure mechanism in large lateral displacements of gravity quaywalls during earthquakes. The results show that the Mononobe–Okabe theory underestimates the resultant of earth pressure from the liquefied submerged backfill. For the cases of the two earthquakes studied in this paper, several dimensionless parameters obtained by using the proposed simple model have similar values.