喷涂式轻质砂浆-冷弯薄壁型钢组合墙体抗剪性能试验研究

摘要

对4个喷涂式轻质砂浆-冷弯薄壁型钢组合墙体足尺试件进行低周反复加载试验，研究型钢骨架类型和立柱轴压比对墙体抗剪性能的影响，分析试件的受力过程和破坏模式，对试件的承载能力、抗侧刚度、延性、刚度退化以及承载力退化等力学特征进行研究；并对喷涂式轻质砂浆-冷弯薄壁型钢组合墙体抗剪承载力设计值的确定进行初步探讨。研究结果表明：墙体的主要破坏模式为边立柱底部的局部受压屈曲和型钢骨架与两侧轻质砂浆之间的滑移失效；斜撑对墙体的抗侧刚度影响较小，对斜撑节点进行加强可以提高墙体的抗剪承载力；增加立柱轴压比将提高墙体的抗侧刚度，但承载能力和延性有所降低。采用“等安全系数”原则，基于试验数据初步确定喷涂式轻质砂浆-冷弯薄壁型钢组合墙体在多遇水平地震作用下的抗剪承载力设计值。%Through tests of four full scale specimens of cold-formed thin-wall steel framing walls with sprayed lightweight mortar,the influence of the type of cold-formed thin-wall steel frames and axial compression ratio of studs on the shear resistance of walls were investigated. The failure process and pattern of specimens are observed. The mechanical behavior,such as bearing capacity,lateral stiffness,ductility,stiffness degradation and strength degradation are studied. The design values of cold-formed thin-wall steel framing walls with sprayed lightweight mortar are initially discussed. The results indicate that the main failure modes of walls are local compressive buckling at the bottom of side studs and the slips between the steel frames and lightweight mortar on both sides. The lateral stiffness is little affected by diagonal braces,while the shear capacity of the wall increases if the joints are strengthened. Meanwhile,with the increase of axial compression ratio of studs,the lateral stiffness could be improved,but the bearing capacity and ductility are reduced slightly. Based on the principle of equivalent safety coefficient and experimental data,the design values of cold-formed thin-walled steel framing walls with sprayed lightweight mortar are suggested initially under frequently occurred horizontal earthquake actions.