为研究冻融大气环境下构造柱-圈梁约束砖砌体墙的抗震性能,利用气候模拟实验室对4片组合单墙片和4片组合双墙片试件进行了加速冻融试验,进而对其进行了拟静力加载试验.试验结果表明:试件在低周反复荷载作用下均表现为剪切破坏,冻融环境对砖砌体组合墙的破坏形态有一定影响;随着冻融循环次数的增加,试件的开裂荷载和极限荷载不断降低,刚度及耗能能力逐渐退化,而开裂位移和极限位移逐渐增加;冻融循环次数相同时,组合双墙片的承载能力、变形能力和耗能能力均高于组合单墙片,其滞回曲线更加饱满,延性系数约为组合单墙片的1.2倍,刚度退化速率明显降低,表明在冻融环境下设置多道构造柱可有效提高砖砌体组合墙的抗震性能.建立了考虑冻融循环作用次数的砖砌体组合墙受剪承载力公式,且计算结果与试验结果吻合较好.%In order to study aseismic behaviors of composite walls under freeze-thaw environment,accelerated freeze-thaw tests for 4 pieces of single-span combined walls and 4 pieces of double-span combined walls were conducted by applying the technique of accelerated freeze-thaw artificial climate lab,and then their quasi-static loading tests were conducted.The results showed that the specimens' damage mode is shear failure under lower cyclic loadings,the freeze thaw environment has an influence on the failure mode of composite walls;with increase in freeze-thaw cycles,the specimens' crack load and ultimate load drop,their stiffness and energy-dissipating capacity are degenerated gradually,their cracking displacements and ultimate displacements increase gradually;under the same freeze-thaw cycles,the loadbearing ability and energy-dissipating capacity of double-span combined walls are relatively higher than those of singlespan combined walls,the former's hysteretic curve is more fat,their ductility coefficient is 1.2 times of that for singlespan composite walls,the former's stiffness degenerating rate drops obviously;their ultimate load-bearing capacity,deformation capacity and aseismic behaviors are effectively improved using tied columns.Finally,the formula for shearbearing capacity of composite walls was derived under freeze-thaw cycles,the calculation results agreed well with test data.
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