OPENSEES(Open System for Earthquake Engineering Simulation)中的节点"宏模型"是一种模拟钢筋混凝土梁柱节点较为理想的高效单元模式,但目前该模型中确定节点核心区剪切应力应变关系的两种常用方法:修正斜压场理论(MCFT)...OPENSEES(Open System for Earthquake Engineering Simulation)中的节点"宏模型"是一种模拟钢筋混凝土梁柱节点较为理想的高效单元模式,但目前该模型中确定节点核心区剪切应力应变关系的两种常用方法:修正斜压场理论(MCFT)和斜压杆模型,均存在不足;本文提出了能全面反映节点三种传力机理的拉-压杆模型方法来确定剪切应力-应变关系,并推导了该模型的变形协调条件、平衡方程。通过分析比较,拉-压杆模型方法的计算结果与相应的梁柱节点试验结果吻合较好,能在节点配箍率变化较大的范围,更好地反映核心区的剪切应力应变关系。展开更多
In order to evaluate the seismic behavior of confined RC column-composite beam joints, five interior joints were tested under low cyclic reversed load. The weakening extent of flanges, the number of studs, and whether...In order to evaluate the seismic behavior of confined RC column-composite beam joints, five interior joints were tested under low cyclic reversed load. The weakening extent of flanges, the number of studs, and whether to reinforce weakened flanges were used as parameters in designing these five joints. Failure characteristics, hysteretic curves, skeleton curves, ductility, energy dissipation, strength degradation, and stiffness degradation were analyzed. The test results revealed that the steel beam flanges in the joints were equivalent to the tie rod. Weakened flanges resulted in poor seismic behavior; however, the seismic behavior could be improved by increasing studs and reinforcing weakened flanges. The joint steel plate hoops, equivalent to stirrups, did not yield when the maximum load was reached, but yielded when the failure load was reached for the joints with shear failure. Increasing stud-type joints and reinforcing flange-type joints ensured good seismic behavior and met project requirements. Based on the experimental results, the failure mechanism of the joints was discussed, and the shear capacity equations of the joints was presented.展开更多
文摘OPENSEES(Open System for Earthquake Engineering Simulation)中的节点"宏模型"是一种模拟钢筋混凝土梁柱节点较为理想的高效单元模式,但目前该模型中确定节点核心区剪切应力应变关系的两种常用方法:修正斜压场理论(MCFT)和斜压杆模型,均存在不足;本文提出了能全面反映节点三种传力机理的拉-压杆模型方法来确定剪切应力-应变关系,并推导了该模型的变形协调条件、平衡方程。通过分析比较,拉-压杆模型方法的计算结果与相应的梁柱节点试验结果吻合较好,能在节点配箍率变化较大的范围,更好地反映核心区的剪切应力应变关系。
基金Supported by the National Natural Science Foundation of China(No.51209094)
文摘In order to evaluate the seismic behavior of confined RC column-composite beam joints, five interior joints were tested under low cyclic reversed load. The weakening extent of flanges, the number of studs, and whether to reinforce weakened flanges were used as parameters in designing these five joints. Failure characteristics, hysteretic curves, skeleton curves, ductility, energy dissipation, strength degradation, and stiffness degradation were analyzed. The test results revealed that the steel beam flanges in the joints were equivalent to the tie rod. Weakened flanges resulted in poor seismic behavior; however, the seismic behavior could be improved by increasing studs and reinforcing weakened flanges. The joint steel plate hoops, equivalent to stirrups, did not yield when the maximum load was reached, but yielded when the failure load was reached for the joints with shear failure. Increasing stud-type joints and reinforcing flange-type joints ensured good seismic behavior and met project requirements. Based on the experimental results, the failure mechanism of the joints was discussed, and the shear capacity equations of the joints was presented.
