自复位装配式混凝土框架结构抗震性能试验研究

Experimental Research on Seismic Performance ofSelf-centering Prefabricated RC Frame Structures

提出了一种采用新型连接节点构造的自复位装配式混凝土框架结构。设计并制作了两榀单层单跨框架结构试件,包括一榀现浇混凝土框架和一榀新型装配式混凝土框架。其中,对装配式混凝土框架结构进行了两次拟静力试验,第二次试验是在第一次试验完成后并更换结构的耗能钢筋进行的。试验结果表明:新型装配式混凝土框架结构的承载能力和耗能能力略低于现浇混凝土框架结构,但延性较现浇框架有较大提高,层间位移角超过1/50时,承载力仍无下降趋势;另外,装配式混凝土框架结构在第一次试验后的残余变形约为现浇框架结构的15%,构件损伤轻微,结构可以实现自主复位;装配式框架结构在第二次试验中的承载力较第一次试验略有下降,残余变形有所增大,仍然具有一定的自主复位能力,结构损伤仍较轻微,说明其经过简单地更换耗能钢筋就可以实现抗震能力的基本恢复。

A new self-centering prefabricated RC frame structure was proposed.Two single-floor and one-bay frame specimen were designed and constructed,including one cast-in-situ concrete frame and one new type of prefabricated RC frame.Two quasi-static tests were carried out for the self-centering prefabricated RC frame specimen,and the second test was carried out after the completion of the first test and the energy-dissipation rebars of the structure were replaced.The results showed that the bearing capacity and energy-dissipation capacity of the new prefabricated RC frame was slightly lower than the conventional concrete frame,but the ductility was enhanced substantially compared with the conventional concrete frame.When the drift ratio was larger than 1/50,the bearing capacity of the prefabricated RC frame still did not decrease.The residual deformation of the new prefabricated RC frame after the first quasi-static test was approximately 15%of that of the cast-in-situ concrete frame.The damage degree of the components was slight and the self-centering performance of the structure could be achieved.The bearing capacity of the new prefabricated RC frame in the second test was decreased slightly,and the residual deformation was larger compared with the results of first test.The self-centering performance still existed,and the damage degree of component was still slight.It could be shown that the seismic performance of the new self-centering prefabricated RC frame could be basically restored through the simple replacement of the energy-dissipation rebar.