自密实再生块体混凝土叠合剪力墙抗震性能试验研究

为了对再生块体混凝土叠合剪力墙的安全性鉴定和抗震加固提供参考，通过1片预制普通混凝土墙板内现浇自密实混凝土叠合剪力墙和3片预制普通混凝土墙板内现浇自密实再生块体混凝土叠合剪力墙的低周反复荷载试验，研究了不同废旧混凝土块体取代率、轴压比和边缘约束构件钢管厚度对剪力墙抗震性能的影响，对比分析了各剪力墙的破坏形态、滞回曲线、骨架曲线、刚度退化及耗能能力。研究结果表明：预制墙板自密实再生块体混凝土叠合剪力墙与预制墙板自密实混凝土叠合剪力墙均具有较好的抗震性能；两侧预制墙板之间虽然没有设置格构式钢筋，但通过预制墙板内侧界面锯齿状处理方式以及端部钢管混凝土构件的约束，使预制和现浇的叠合墙体能整体协同受力；自密实再生块体混凝土叠合剪力墙的承载能力与自密实混凝土叠合剪力墙的相当；废旧混凝土的掺入对叠合墙体初始刚度、水平承载力、骨架曲线、耗能能力、刚度、破坏位移角和延性的影响不大；在试验参数范围内，钢管厚度和轴压比在一定范围内的增加，有利于改善叠合墙体承载力，提高叠合墙体耗能能力。建立了钢管混凝土边缘约束自密实再生块体混凝土叠合剪力墙的承载力计算式，计算结果与实测结果吻合较好。

Experimental study on seismic behavior of composite shear walls filled with demolished concrete lumps and self-compacting concrete

To provide theoretical basis and technical support for safety appraisal and seismic strengthening of composite structure filled with demolished concrete lumps (DCLs), the seismic performance of one precast normal concrete (NC) composite shear wall infilling self-compacting concrete (SCC) and three precast NC composite shear walls infilling DCLs and SCC were studied under quasi-static tests. The influences of various parameters (mix ratio of demolished concrete, axial load ratio and steel tube thickness of end post) on the seismic behavior of specimens were investigated. The failure pattern, hysteretic loops, skeleton curves, stiffness degradation curves and energy dissipation of shear walls were analyzed and compared. The test results indicate the two types of composite shear walls have good seismic behavior. Although no lattice reinforcement is set between the two sides of precast walls, the precast and cast-in-place composite walls can cooperate with each other through the zigzag treatment of the inner interface of the precast walls and the constraint of the end concrete-filled steel tube.The carrying capacity of composite shear wall infilling DCLs and SCC is not lower than that of composite shear wall infilling SCC. The addition of DCLs has little effect on the initial lateral stiffness, lateral load carrying capacity, skeleton curve, energy dissipation capacity, stiffness, destructive drift ratio, and ductility of composite shear walls. In addition, the increase of steel tube thickness and axial load ratio in a certain range can improve the carrying capacity and energy dissipation capacity of shear walls within the test range. The equations for predicting the strength of the new DCLs and SCC filled tube-confined composite shear wall were proposed. The calculated strengths are in good agreement with the test results.