灌浆套筒连接装配式混凝土柱抗撞性能研究
Impact performance of precast concrete columns with grouted sleeve connection
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摘要: 为研究撞击荷载下灌浆套筒连接装配式混凝土(Precast Concrete, PC)柱的力学性能和损伤机理,采用数值仿真技术建立了 PC 柱精细有限元模型,并完成了模拟方法的验证,分析了 PC 柱的撞击响应特征与传统现浇混凝土(Cast?in?Place Concrete, CIPC)柱的差异,讨论了撞击位置、轴压力、接缝强度和套筒连接强度等参数对 PC 柱抗撞性能的影响,并从曲率分布的角度分析了 PC 柱的损伤特性。结果表明:相同撞击条件下 PC 柱和 CIPC 柱的非线性力学行为比较接近,但两者柱底的传力机制和破坏形态差异明显;曲率分布能直观描述 PC 柱的损伤细节特征;撞击位置的变化会改变 PC 柱的抗力机制,而轴压比在一定程度上可提高 PC 柱抗撞能力;由于撞击荷载的局部效应显著,接缝强度和套筒连接强度主要影响接缝附近柱体的损伤机理。Abstract: To numerically investigate the mechanical properties and damage mechanism of precast concrete (PC) columns with grouted sleeve connection subjected to impact loadings, the refined finite element model of PC column under lateral impact was established and verified against previous impact test results. The differences between the impact response characteristics of PC columns and cast-in-place concrete (CIPC) columns were studied. The influence of impact position, axial load ratio, strengths of joint and grout sleeve connection on the impact performance of PC columns was examined, and the damage characteristics of PC columns were analyzed from the perspective of curvature distribution. The results show that PC column and CIPC column exhibit similar nonlinear mechanical behaviors under the same impact conditions. However, the force transfer mechanism and failure patterns of the columns below the impact point are quite different. In addition, the curvature distribution could be utilized to describe the damage concentrations of the impacted columns. The change of impact position will vary the resistance mechanism of PC columns,and the axial load ratio can improve the anti-impact capacity of PC columns to a certain extent. Due to the significant local effect of impact loadings, the strengths of joint and grout sleeve connection mainly affect the damage mechanism of the column near the joint.