预制RC框架内嵌带竖缝剪力墙结构抗震性能研究

Study of seismic behavior of precast RC frame with infill slit shear walls

为研究预制钢筋混凝土框架内嵌带竖缝剪力墙(PRCFW)结构的抗震性能,对2个单跨两层、缩尺比为1∶2的PRCFW试件进行了拟静力试验研究。考察了PRCFW结构的变形和延性、滞回耗能能力、承载力及刚度退化等性能,分析了框架与内填墙之间的抗剪连接件对结构整体性能的影响。试验结果表明:在加载过程中,设计的抗剪连接件性能可靠,未发生疲劳剪断或锚固破坏;内填墙设置竖缝对PRCFW结构的初期刚度影响较小;进入屈服段后,预制竖缝阻碍了斜裂缝的发展和贯通,缝间墙段以弯曲变形为主,承载力和刚度退化缓慢,使结构整体具有良好的延性和耗能能力。不同轴压比下的框架柱和现浇节点基本完好,破坏主要发生在内填墙和梁端。结合试验和分析结果,提出了PRCFW结构在工程设计时的若干补充计算及构造措施建议。

Quasi-static tests were performed on two one-bay,two-story specimens built at one-half scale to study the structural cyclic behavior of precast reinforced concrete frame with infill slit shear walls( PRCFW). Overall behaviors of the PRCFW structure such as deformation and ductility,energy dissipation capacity, strength and stiffness degradation were inspected. Influence of the shear connectors between the frame and infill walls on the overall structural behavior was also analyzed. Experimental results show that the designed shear connectors perform well during the loading process,and no shear fatigue failure or anchorage failure occurs. Prefabricated vertical slits in the infill walls have little effect on overall elastic stiffness of the specimen,but the vertical slits prevent the development and penetrating of diagonal cracks. The main deformation of the wall segments between vertical slits is bending deformation after the structure yields. The post-peak strength and stiffness decrease slowly,which offers the whole PRCFW structure a good ductility and energy dissipation capacity. Columns under different axial compression ratios and cast-inplace joints basically remain intact,while damage mainly occurs in the infills walls and beam ends,satisfying the principle of ‘strong joint-weak component,strong column-weak beam ' and the design prospective of dissipating earthquake energy by the damage of infills walls. Based on the test and analysis results,a few design recommendations including supplementary design rules and detailing requirements for this type of structure are proposed at last.