抄録
In this paper, we investigate the seismic performance of existing reinforced concrete buildings, the damage prediction and the actual concrete strength based on the seismic diagnosis results from 1996 to 2006 in Hokkaido. The following conclusions are obtained: (1) 79% of buildings built before 1971 do not satisfy the sesmic capacity index Is≥0.6; (2) The average ratio of actual concrete strength by core tests to design basis one is 1.39; (3) The seismic retrofit of buildings reduces the predicted seismic damage ratio over moderate damage rank to approximately one fourth as compared to the non-retrofit buildings under the earthquake ground motion level of JMA seismic intensity of 6.
