受火后套筒灌浆连接装配式混凝土剪力墙抗震性能试验研究

Experimental study on seismic performance of prefabricated concrete shear walls connected with sleeve grouting post fire

为了研究火灾后套筒灌浆连接装配式混凝土剪力墙的抗震性能,对4榀受火后套筒灌浆连接装配式混凝土剪力墙、1榀受火后现浇剪力墙对比试件及1榀常温未受火套筒灌浆连接剪力墙对比试件进行低周反复加载试验,研究受火时间、暗柱设置、套筒灌浆连接方式对套筒灌浆连接混凝土剪力墙的破坏形态、承载力、刚度、延性、耗能能力的影响。试验结果表明:与常温未受火套筒灌浆连接剪力墙相比,受火后套筒灌浆连接剪力墙在低周往复拟静力加载过程中会出现混凝土塌落现象,受火60、113 min的套筒灌浆连接剪力墙承载力分别降低4.68%、13.15%,位移延性系数分别降低2.56%、7.73%,初始刚度分别降低9.92%、27.73%;在相同受火时间下,暗柱对受火后套筒灌浆连接混凝土剪力墙的承载力影响不大,但可以增加刚度、延性和耗能能力;与现浇剪力墙相比,受火113 min后套筒灌浆连接剪力墙承载力降低20.72%,初始刚度降低9.33%,位移延性系数增加4.68%,在屈服前耗能能力优于现浇剪力墙,在屈服后耗能能力劣于现浇剪力墙。

In order to study the seismic performance of prefabricated concrete shear walls with sleeve grouting connection after exposure to fire,low-cycle reversed loading tests were conducted on four prefabricated concrete shear walls with sleeve grouting connection after fire,one cast-in-place shear wall contrast specimen after fire and one prefabricated shear wall contrast specimen with sleeve grouting connection at room temperature.The effects of fire durations,concealed column setting and sleeve grouting connection form on the failure mode,bearing capacity,stiffness,ductility,and energy dissipation of sleeve grouting connected concrete shear walls were studied.The test results show that compared with the shear wall connected with sleeve grouting under room temperature,the phenomenon of concrete collapse occurs during the low cycle reciprocating quasi-static loading process of shear walls connected by sleeve grouting after exposure to fire.For the shear walls connected with sleeve grouting exposed to fire for 60 min and 113 min,the bearing capacity decreases by 4.68%and 13.15%,respectively.The displacement ductility coefficient decreases by 2.56%and 7.73%,respectively,and the initial stiffness decreases by 9.92%and 27.73%,respectively.Under the same fire exposure time,the presence of concealed columns has almost no effect on the bearing capacity of sleeve grouting connected concrete shear walls after exposure to fire,but can increase stiffness,ductility,and energy dissipation capacity.Compared with the cast-in-place shear wall,the bearing capacity of the sleeve grouting connected shear wall after exposure to fire for 113 min is reduced by 20.72%,the initial stiffness is reduced by 9.33%,and the displacement ductility coefficient is increased by 4.68%.The energy dissipation capacity is better than that of the cast-in-place shear wall before yielding,and is worse than that of the cast-in-place shear wall after yielding.