Parameter identification of hysteresis model of reinforced concrete columns considering shear action

Abstract

It is necessary to determine the load-displacement hysteresis relationship of the reinforced concrete (RC) columns to accurately predict the nonlinear dynamic response of RC columns during earthquakes. In this paper, 17 rectangular RC columns were tested under horizontal cyclic loading and the hysteresis characteristics of RC columns considering shear action were obtained. Then, the influences of Bouc-Wen-Baber-Noori (BWBN) restoring force model parameters on the hysteresis loops of RC columns were analyzed. Based on the quasi-static test data of rectangular RC columns failed in flexural-shear and shear collected from the PEER-Structural Performance Database and the tests in this paper, a parameter identification method for the BWBN model of RC columns was proposed. After that, the probability distribution and the statistical value of the major influencing parameters of BWBN model for shear-dominated RC columns were calculated. The results show that the BWBN model can accurately predict the hysteresis loops of RC columns under cyclic loading and describe the hysteresis characteristics of shear-dominated RC columns, such as strength, stiffness degradation, and pinch effect. The proposed method can identify BWBN model parameters for shear-dominated RC columns well, and the main distribution range of strength degradation parameter δv, stiffness degradation parameter δη, and pinch effect parameter ζs increase gradually with the failure mode of RC columns from flexural-shear failure to shear failure, indicating that the degradation and pinch effect of RC columns failed in shear is more significant than that of flexural-shear. The presented approach is also appropriate for other components or structures, which lays a foundation for further seismic dynamic response analysis.