Development of an Evaluation Method for Seismic Isolation Systems of Nuclear Power Facilities

Abstract

In this study, static loading tests were conducted in order to investigate ultimate seismic performance of reinforced concrete foundation (pedestal) for seismic isolated nuclear power plant. Half-scale four test specimens, which consist of Lead Rubber Bearings (LRBs) of 800mm in diameter and reinforced concrete pedestals of 1200mm 1200mm in horizontal view, were used with the parameters of cyclic pattern of axial stress of seismic isolator, existence or non-existence of reinforcing bars at the top of pedestal, and concrete compressive strength. As a result of the study, it was confirmed that the reinforced concrete pedestal shows structural integrity within design level loads. In ultimate level loads, no damage was observed in the case of non-variable axial stress in the area near the center of buildings, and no brittle failure was observed and supporting function of axial loads was retained in the area near the outer edge of buildings, where variable axial stress in ultimate level was extremely large.