基于纤维梁柱单元的钢筋混凝土柱往复荷载作用下破坏过程分析

为高效准确地模拟往复荷载作用下钢筋混凝土构件的破坏过程,基于结构精细化模拟分析平台(RSAPS)中的纤维梁柱单元模型,建立一种考虑损伤破坏的钢筋本构模型,并构建了材料破坏准则,从而建立了钢筋混凝土构件受力破坏的分析方法。应用RSAPS平台对钢筋混凝土柱往复加载试验进行模拟,结果表明考虑钢筋损伤破坏的模型可以很好地模拟构件的刚度和承载力退化过程,模拟结果与试验结果更为吻合;进一步对往复荷载作用下钢筋混凝土柱的破坏过程进行模拟分析,结果表明考虑钢筋损伤破坏的模型能够准确地模拟由于局部材料失效破坏导致的钢筋混凝土构件承载力退化、耗能能力降低等非线性行为,可以较好地描述往复荷载作用下钢筋混凝土构件的破坏过程,可用于地震作用下建筑和桥梁结构倒塌过程分析。

Analysis of Failure Process of RC Columns Under Cyclic Loading Based on Fiber Beam-Column Element

In order to simulate the failure process of reinforced concrete (RC) members under cyclic loading precisely and effectively, based on the fiber beam-column element in refined simulation analysis platform of structures (RSAPS), a steel constitutive model considering the material damage was developed, and failure criterion for concrete and steel reinforcement were proposed. Thus, a failure analysis method for reinforced concrete (RC) members under loading was established. Pseudo-static tests of RC columns were simulated using the platform RSAPS. The results indicate that the model considering the material damage can capture the behavior of stiffness and strength stiffness degradation of columns, and the response predicted with the developed model shows a very good correlation with the experimental results. Then, the failure process of a RC columns under cyclic loading was simulated. The results indicate that the model considering the material damage can accurately capture the nonlinear behavior, such as strength degradation and energy dissipation reduction of columns induced by local material failure, and the failure process of RC column under cyclic loading. The proposed method can be used for analyzing the collapse process of buildings and bridges subject to earthquake motion.