Abstract
Nagoya Port is eminent trade port in Japan. In order to maintain the function of Nagoya Port, many dredged soils must be currently filled every year at Nagoya Port Island (hereinafter, PI) as a temporary disposal area. However, a huge earthquake would damage a revetment of PI to flow large volumes of dredged soils into the harbor. This would lead directly to a functional depression of Nagoya Port. For this reason, seismic assessment of PI and improvements to their earthquake resistance are urgent issues. In this study, we conducted a numerical simulation to grasp not only the damage of PI during and after the largest envisioned Nankai Trough earthquake but also the effect of height of reclaimed land on the deformation of PI due to the earthquake. The main conclusions are as follows. 1) If the current situation remains unchanged, a large deformation would occur on the PI by the earthquake, but the damage extent would not be such that dredged soils would flow into the harbor. 2) If the existing height were raised by 4 m, it would be impossible to prevent the lateral displacement of dredged soils, and there would be a high risk of dredged soils flowing into the harbor. 3) If the height were 4m lower than existing height, the lateral desplasement of dredged soils and revetment is reduced. These results indicated that it is dangerous that the height of the reclaimed land was raised more and it is important that the height of reclaimed land is reduced as much as possible for PI earthquake resistance.
