接缝处理方式对复合齿槽连接预制剪力墙抗震性能的影响

Effect of Joint Treatment on the Seismic Performance of Prefabricated Shear Wall with Composite Alveolar

为研究水平接缝处不同处理方式对复合齿槽连接预制剪力墙抗震性能的影响,对3片足尺预制剪力墙的水平接缝分别采取普通凿毛、加设型钢抗剪键及增大穿过接缝的钢筋直径3种处理方式的复合齿槽连接预制剪力墙试件进行拟静力试验,观察各试件最终破坏形态,对比分析其滞回曲线、骨架曲线、承载力、耗能能力、延性、刚度退化和钢筋应变的差异.结果表明:所有试件破坏模式均为预制墙体两侧暗柱纵筋受压屈服或拉断、墙体两侧角部混凝土压溃剥落的压弯破坏;预制试件的位移延性系数均大于4,极限位移角为1/51~1/42;各试件齿槽处U型钢筋搭接连接锚固可靠,能有效地传递钢筋应力;增设型钢抗剪键及增大穿过接缝的钢筋直径的试件其滞回曲线更加饱满,承载力、耗能能力及初始刚度均有较大提高,有更好的抗震性能;水平缝处增设型钢抗剪键的预制试件YZW2拥有更好的墙体变形能力,墙体延性更好,能够更好地提高预制墙体抗剪能力和整体的工作性能,避免发生剪切滑移;增大钢筋直径的预制试件YZW3拥有更高的初始刚度,墙体开裂延迟,在工程中更便于施工操作.

To investigate the influence of different treatment methods for horizontal joints on the seismic performance of prefabricated shear walls with composite alveolar,pseudo-static tests were conducted on the prefabricated shear wall specimens with three horizontal joints of full-scale precast shear walls,which were treated with a common chisel,by adding a steel shear key,and by increasing the diameter of the steel bar passing through the joints.The final failure patterns of each specimen were observed.The differences of the hysteresis curve,skeleton curve,bearing capacity,ductility,stiffness degradation,and steel bar strain were compared and analyzed.Results show that the failure modes of all specimens are tensile yield of the longitudinal reinforcements in the concealed column and compressive failure of concrete at the bottom of the wall.The displacement ductility ratio of the prefabricated specimens is greater than 4,and the ultimate drift ratios of precast specimens range from 1/51 to 1/42.The U-type steel overlap in the composite alveolar area of each specimen is reliable and can effectively transfer the stresses of vertical reinforcement.The hysteresis curve of the specimen with the steel shear key and the large-diameter reinforcing bar passing through the joint is fuller than that of the other specimens,and its bearing capacity,energy dissipation capacity,and initial stiffness are considerably improved.Compared with the other specimens,the prefabricated specimen YZW2 with steel shear key at the horizontal joint has better wall deformation capacity and better wall ductility,which can improve the shear resistance and overall working performance of the precast wall to avoid shear slip.Compared with the other specimens,the prefabricated specimen YZW3 with reinforcing bar at the horizontal joint has higher initial stiffness and better performance on delaying wall cracking,which ensure convenience during engineering operation.