Abstract
In the performance based design, it is important to evaluate deformation performance capacity of structures. Deformation performance capacity of piles, however, should be considered by focusing more on the relation between subgrade and deformation performance capacity of shaft. In this study, a series of RC pile cap loading tests in air and dense sand are conducted by focusing on deformation performance capacity of RC pile cap, which often has serious damage during earthquake. As the result, ductility capacity is little dependent on subgarde, but restoring force is subjected to lateral resistance of subgrade, and the problem to lateral resistance of subgrade at design code for railway structures is presented.
