带耗能钢板的自复位方钢管混凝土框架抗震性能研究

为了减小“梁增长”现象对自复位框架的影响，提出一种自复位方钢管混凝土框架，该框架由钢管混凝土柱、钢梁及带耗能钢板的自复位梁柱节点组成。对3榀1/3比例的自复位方钢管混凝土框架进行低周往复荷载试验，研究其自复位性能和抗震性能。利用有限元软件ABAQUS对其进行了非线性数值分析，并验证了有限元模型的准确性，同时构建足尺模型研究了钢绞线初始预拉力和耗能钢板耗能段截面积对自复位框架性能的影响。结果表明：加载至2%层间位移角时，自复位框架表现出较好的自复位能力和耗能能力；增大钢绞线初始预拉力，结构承载能力与耗能能力增强，自复位能力先增强后减弱；增大耗能钢板耗能段截面积，结构的承载力随之增大，残余变形亦增大，自复位能力减弱。

Seismic behavior of self-centering concrete-filled square steel tubular frame with energy dissipating steel plates

In this paper, a novel self-centering concrete-filled square steel tubular (SC-CFST) frame composed of CFST columns,steel beams and self-centering connections with energy dissipating steel plates was proposed to reduce the negative effects of the so-called beam expansion. Low cyclic loading tests were carried out on three 1/3 scaled SC-CFST frames to investigate the self-centering and seismic behaviors. Nonlinear analysis was also conducted on SC-CFST frames using the finite element package ABAQUS, which was verified by comparing the nonlinear analysis results and the test results. The effects of the initial posttensioning force and the section area of energy dissipating plates on the performance of the SC-CFST frame were also studied using the full-scale finite element model. The results show that these structures have good self-centering ability and energy dissipating capacity under a inter-story drift of up to 2%. Besides, with the increase of initial posttensioning force, the load capacity and energy dissipation capacity of the SC-CFST frame increase, while the self-centering ability increases at the beginning and decreases later. Increases in the section area of energy dissipating steel plate lead to increases in the lateral bearing capacity, while bring more residual drift and cause reduction in the self-centering capacity of the structure.