半装配式再生混凝土低矮剪力墙抗震性能试验

Test on seismic behavior of semi-assembled low-rise recycled concrete shear walls

为研究半装配式单排配筋混凝土剪力墙结构的抗震性能以及再生混凝土在预制剪力墙中的应用效果,设计了4个不同轴压比下工字形半装配式单排配筋普通混凝土和再生混凝土剪力墙试件,试件由底部带预留孔的上层预制剪力墙、带墩头竖向分布钢筋的基础梁、二者之间的坐浆层以及纵横墙交接处的现浇暗柱组成,基础梁顶部伸出的单排竖向墩头钢筋伸入上层预制墙体底部的预留孔中,采用灌浆锚固的方法连接,并进行了低周反复荷载试验,分析了各个试件的破坏特征、承载力、刚度以及耗能等.结果表明:在水平荷载作用下,预制剪力墙与基础梁之间的连接部位出现水平通缝并产生较小滑移,墙身分布着X形交叉斜裂缝;随着轴压比的增大,试件的承载力提高,但延性较差;再生混凝土试件的破坏形态和受力性能与普通混凝土试件相近,再生混凝土可用于工厂预制的结构构件中;半装配式单排配筋混凝土剪力墙构造简单、施工方便,且抗震性能良好,可用于低多层剪力墙结构中.

To evaluate the seismic behavior of semi-assembled shear wall with single row of steel bars and the application effect of recycled concrete in the precast shear walls, four I-shaped semi-assembled concrete shear wall specimens with single row of steel bars were designed.This type of specimen consisted of an upper precast concrete shear wall with reserved holes at the bottom, a foundation beam with single row of button-head steel bars, slurry layer between the precast shear wall and the foundation beam, and cast-in-place concealed columns between longitudinal and transversal walls.Button-head steel bars extending from the surface of the foundation beam were anchored in the reserved holes of the precast shear wall, with high strength grouting material filling the holes.Specimens were tested under cyclic reversed loading and different axial compression.Failure character, bearing capacity, stiffness, energy dissipation were compared, and the results show that： under the horizontal load, horizontal crack and a small slip appear in the joint connection between the precast shear wall and the foundation beam, X-shaped cracks distribute in the precast wall;with the increase of axial compression ratio, the bearing capacity of specimens is improved, but the ductility is reduced;the failure mode and mechanical properties of recycled concrete specimens are similar to those of normal concrete specimens;the semi-assembled shear wall structure with single row of steel bars has the advantages of simple structure, convenient construction and good seismic performance, and it can be used in low-rise and multistory residential structures.