多层砌体结构窗下墙破坏模式试验研究

In-plane experimental study on seismic behavior of multi-storey masonry wall

为验证多层砌体结构开洞墙体窗下墙破坏模式震害现象,设计缩尺比例为1:3的三层三跨砌体结构开洞墙体试件,对其进行拟静力低周往复加载试验。分析多层砌体墙体窗下墙破坏模式的破坏特征,研究整体墙及各层墙体的滞回特性、骨架曲线、刚度退化规律、耗能特性、延性与变形特征等抗震性能。试验结果表明:发生窗下墙破坏模式的开洞墙体破坏过程分为裂缝出现、变形发展与强度退化三个阶段;窗下墙作为第一道抗震防线可提前参与整体结构耗能、降低墙体刚度退化速率、增加整体墙的延性和变形能力,其破坏模式相对窗间墙破坏模式更为合理。研究结果揭示了发生窗下墙破坏模式墙体的抗震性能与变形特征,为实现砌体结构合理破坏机制提供依据。

In order to verify the spandrel failure pattern of multi-storey masonry wall with openings, a three-story and three-bay masonry model with a scale ratio of 1:3 was designed for the quasi-static low-cycle loading test. The failure process and characteristics of the multi-story masonry model were analyzed. Additionally, the hysteretic behavior, skeleton curve, stiffness degradation, deformation, ductility and energy dissipation of the overall wall and the wall at each floor were studied. The test results indicate that the process of spandrel failure wall can be divided into three stages: crack emergence, deformation development and strength degradation. As the first seismic fortification line, spandrels can participate in the overall structural energy dissipation in advance, reduce the rate of stiffness degradation and increase the ductility and deformation capacity of the overall wall, which make its failure pattern more reasonable compared with that of pier. The research results exhibit the good seismic behaviors and deformation characteristics of the spandrel failure wall, which provide the basis for achieving the reasonable failure mechanism of the masonry structures.