REDUCTION OF CAISSON EDGE PRESSURE IN COMPOSITE-TYPE BREAKWATER REINFORCED BY EMBANKMENT

Abstract

 The method to pile up stones behind a caisson is gathering attention after Great East Japan Earthquake for reinforcing breakwaters against a tsunami. Past experiments and analyses showed that piled stones could increase the sliding resistance and bearing capacity of foundation mound. The assessment method was also proposed. However, there is few research that investigated subgrade reaction acting on the bottom of a caisson backfilled with stones. Large edge pressure might damage the corner of a caisson and crush stones. In this study, subgrade reaction of a caisson was examined by centrifuge model tests. The edge pressure was comprehensively examined on the basis of the test results of the present and past studies. Simplified model calculating the subgrade reaction could successfully simulate the model tests.