设置自复位支撑的钢筋混凝土框架结构抗震性能研究

SEISMIC PERFORMANCE STUDY OF REINFORCED CONCRETE FRAME WITH SELF-CENTERING BRACES

提出了一种能准确描述预压弹簧自复位耗能(PS-SCED)支撑滞回性能的力学模型,引入状态变量区分支撑不同工作阶段从而确定其力学响应。基于ABAQUS平台对该力学模型进行二次开发,将开发的PS-SCED支撑单元模拟结果与支撑力学性能试验结果进行对比,并对设置PS-SCED支撑的3层钢筋混凝土框架结构进行抗震性能分析。结果表明:该支撑单元模拟得到的滞回曲线与试验结果吻合较好,可准确描述支撑在动力荷载作用下的力学性能;强震作用下,PS-SCED支撑能够充分耗散地震能量,有效控制结构的塑性变形;此外,PS-SCED支撑框架结构相比于原框架结构残余变形减小了72.1%~92.1%。PS-SCED支撑具备良好的耗能能力和自复位特性,能够显著提高钢筋混凝土框架结构的抗震性能。

A mechanical model is proposed accurately describe the hysteretic behavior of pre-pressed spring self-centering energy dissipation(PS-SCED)brace.The state variables are introduced to distinguish different stages of PS-SCED brace and then its mechanical responses are determined.The secondary development of the mechanical model is carried out based on ABAQUS.The simulation results of the developed PS-SCED brace element are compared with the test results of the brace,and the seismic performances of a 3-story reinforced concrete frame structure with PS-SCED braces are analyzed.The results indicate that the hysteretic curves obtained from the brace element simulation agree well with the test results,and the brace element is accurate enough to describe the mechanical performance of the brace under dynamic loads.The seismic energy dissipates sufficiently and the plastic deformation of the structure is controlled effectively by PS-SCED braces subjected to strong earthquake.Additionally,the residual deformations of frame structure with PS-SCED braces are reduced by 72.1%~92.1%compared with the original frame structure.The PS-SCED brace exhibits full hysteretic performances with good energy dissipation capacity and self-centering behavior,which significantly improves the seismic performances of reinforced concrete frame structures.