STABILITY OF CAISSON-TYPE QUAY WALL AGAINST TSUNAMI UNDERTOW

Abstract

 Wave forces acting on caisson-type quay walls by undertow of overflowing tsunamis have not been studied sufficiently. Here, hydraulic experiments are performed to examine the tsunami forces and arrange compensating parameters for an estimation formula of the forces. In addition, a solidification method is proposed to enhance the stability of the caissons against the tsunamis. Its good performance is shown by the experiments, and influences of damages of the surrounding structures, e.g. a crack of the solidification part or a tilt of the caisson, are clarified. From the experiments, it was found that the water level inside the solidification part was decreased, and as a result, the tsunami forces on the caisson were effectively reduced by the solidification treatment. Moreover, it was shown that the solidification treatment maintained a more tenacious structure even when the damages of the surrounding structures occurred.