震源近傍の強震記録を用いた1質点系弾塑性モデルの最大応答予測に関する解析的研究

Abstract

Kumamoto earthquakes which occurred on May 14th and 16th in 2016 caused severe damages to some buildings at the central place of Kumamoto city. The epicenters of the earthquakes are only 20km apart from the central place of Kumamoto city. There are some reinforced concrete structures were damaged by the earthquakes. In order to predict the maximum response of the damaged buildings, the seismic response analysis was conducted by using the single-degree-of-freedom system with elastic and plastic behaviors. The strong ground motions recorded at the seismographs near to the damaged building were used to the time history analysis. The maximum elastic response of the restoring force was defined as the maximum capacity P(emax). The main parameter of the analytical study was the ratio of the yield strength to P(emax). The analytical results were compared to the theorical curves based on the assumption of equating the energies between elastic system and elasto-plastic system. The calculated maximum deformations by the numerical analysis showed lower than the predictions by the theory.