内置碟簧自复位钢筋混凝土剪力墙拟静力试验及损伤分析

Quasi-static test and damage analysis on self-centering reinforced concrete shear wall with disc spring devices

为了减小钢筋混凝土剪力墙在地震后的损伤和残余变形,提出了内置碟簧自复位钢筋混凝土剪力墙(self-centering RC shear wall with disc spring devices, SCSW-DSD),通过在墙脚两侧安装碟簧装置为墙体提供恢复力并保护墙脚处混凝土。对1片SCSW-DSD和1片普通混凝土剪力墙进行了拟静力加载试验,对比分析了两者的滞回性能、水平刚度退化、残余位移及损伤演化过程。结果表明:相比普通混凝土剪力墙,SCSW-DSD的水平荷载-位移曲线无下降段,承载力略降低,但SCSW-DSD最大加载位移角达到了3%,最大加载位移提高了44.4%,具有较好的变形能力;在相同加载位移下,SCSW-DSD的残余位移均较普通混凝土剪力墙的小,最大残余位移角减小约65.8%,具有良好的自复位性能;SCSW-DSD裂缝发展较慢且数量较少,其约束边缘纵筋应变小于0.007,水平分布钢筋应变小于0.001,均较普通混凝土剪力墙的小,表明SCSW-DSD损伤程度较小。

In order to reduce the damage and residual deformation of reinforced concrete(RC) shear walls after earthquake, a self-centering RC shear wall with disc spring devices(SCSW-DSD) was developed. The disc spring devices were installed at the bottom corner to provide the restoring force for the wall and protect the concrete at the wall toes from damage. A piece of SCSW-DSD specimen and a piece of traditional RC shear wall specimen were designed and a series of quasi-static loading tests were conducted to compare and analyze the hysteretic behavior, horizontal stiffness degradation, residual displacement and damage evolution process. The results indicate that the horizontal load-displacement curves of the SCSW-DSD have no descending branch and the bearing capacity is slightly reduced compared to the traditional RC shear wall, but the maximum loading drift ratio of the SCSW-DSD reaches 3%, which is 44.4% higher than that of the traditional RC shear wall, indicating that the SCSW-DSD has a better deformation ability. The residual displacement of the SCSW-DSD is smaller than that of the traditional RC shear wall at the same loading displacement, and the maximum residual drift ratio of the SCSW-DSD is reduced by about 65.8%, indicating that the SCSW-DSD specimen has a good self-centering performance. Furthermore, the SCSW-DSD specimen has relatively few cracks, and the cracks develop relatively slowly. The longitudinal rebar strains of the constraint boundary column are less than 0.007, and the horizontal distributed rebar strains are less than 0.001. All strains of the SCSW-DSD are less than those of the traditional RC shear wall, which indicates that the SCSW-DSD specimen has less damage.