Hysteretic Behavior Simulation Based On The Pier Failure Mode

The reinforced concrete (RC) columns are vulnerable to suffer serious damage in earthquake. And columns with different failure modes exhibit different seismic performance. Investigations on the failure mode and seismic performance of RC columns are necessary. Developing the numerical simulation of hysteretic behavior research is the premise and guaranty to reveal the damage mechanism and understand the seismic performance of the bridge piers. Based on the comparison of the existing pier failure mode identification methods, numerical analysis models for different failure modes are established. The main work is as follows:1. According to the experiment data of columns in PEER, which are under cyclic loading, the identification methods proposed by Ma Ying、 Zhu and Liu Ming are compared by 56 test dada of columns, which include flexural failure、 flexural-shear failure and shear failure. The method is comparing the judgment error rate of the three identification methods. The results show that the identification method proposed by Zhu is most suitable used to predict the failure modes of reinforced columns.2. Based on the Two-Zone Column Classification Method, the numerical analysis models of columns with different failure modes are established. A numerical analysis model combination of bending and longitudinal reinforcement pull out effect is established for columns in Zone F. A numerical analysis model combination of bending-shear and longitudinal reinforcement pull out effect is established for columns in Zone S. Through simulating 6 columns with three different failure modes, the established models are verified.3. As the failure mode of hollow columns is difficult to distinguish, a unified formula for seismic deformation capacity of rectangular hollow columns proposed by Sun Zhi-guo is used in the current work. And the formula is achieved though the limit state material provided by Opensees platform. On this basis, a unified hysteretic analysis model for rectangular hollow bridge piers with different failure modes is established. In the model, the unified deformation capacity formula was used to define the initiation of the strength and stiffness degradation as a result of shear or flexural failure. The hysteretic curves for 7 rectangular hollow pier specimens with different failure modes were simulated and compared with experimental results.