Abstract
No matter how the plastic hinge region is confined by ties, a reinforced concrete pier that suffered flexural damage in an extreme earthquake has to be repaired after the earthquake. Since failure of core concrete occurs only at the plastic hinge region, if a stable material under cyclic load excursions could replace the concrete at this region, the pier could perform satisfactorily without failure of concrete. Thus, repair after an earthquake could be eliminated. Based on such a concept, this paper proposes a new pier with a rubber layer at the bottom. Cyclic loading tests for 5 specimens with a 400mm×400mm section was conducted to clarify the performance. Various factors including the effect of confinement of rubber by steel plates and shear key were studied. Fiber element analysis was also conducted to reveal the performance of the new pier. It was found that it is feasible to construct a reinforced concrete pier that has stable hysteresis up to 4% drift without significant damage in the core concrete.
