自复位混凝土剪力墙抗震性能研究进展与展望

强震后工程结构功能快速恢复,是近年来可持续发展工程抗震的重要研究领域.由于通过释放墙片节点约束并沿墙高通长布置并后张无黏结预应力筋实现摇摆回复及倾覆控制,地震动下摇摆和界面张合效应可使自复位混凝土剪力墙表现为无震损或低震损及小残余变形,甚至无残余变形.作为可恢复功能结构体系重要组成部分的自复位混凝土剪力墙结构、技术、理论与设计方法正持续发展.在结构体系上,包括受控摇摆单肢墙、混合摇摆单肢墙、竖向连接耗能联肢墙以及连梁耗能联肢墙结构4种自复位剪力墙,均具备明确的自复位能力,但耗能钢筋/部件组装程度导致了不同结构体系的耗能能力差异明显;在设计方法上,传统的基于力的抗震设计方法难以直接应用,应确定相关性态极限状态和控制点并完善残余变形验算,提出基于位移性态的自复位剪力墙抗震设计方法;非线性分析方法上,纤维模型、集中塑性模型、多弹簧模型以及实体有限元模型等均可较精确地进行自复位剪力墙结构的模拟分析,但仍需有针对性考虑相关参数敏感程度.进而,提出开展预应力筋弹性和非弹性受力行为及其摇摆转动中的变形能力与损失,楼屋盖等水平连接对自复位能力和震损影响,强震下预应力筋和耗能元件失效下自复位剪力墙倾覆,多墙片拼装竖向多节点摇摆的自复位剪力墙高阶振型效应与残余变形预测等四方面研究,为自复位混凝土剪力墙结构体系研发与应用提供理论和技术支撑.

Seismic performance of self-centering concrete shear wall: State-of-the-art review and prospects

Post-earthquake resilience of engineering structures is an important research area of sustainable earthquake engineering in recent years. Restoration and collapse control are realized with the constraint at the base released and the wall panels post-tensioned by unbonded prestressing tendons, which can reduce damage level and even eliminate residual drift owing to the gap-opening mechanism. As an important component of earthquake resilient structural system, self-centering concrete shear wall system is developing continuously. Self-centering shear wall such as controlled rocking wall, hybrid rocking wall, coupled wall with vertical joint, and coupled wall with coupling beam can accomplish restoration, but various dissipating devices result in significantly different levels of energy dissipating. Traditional force-based design is not applicable, so displacement-based performance design should be presented with the improvement of residual drift control, definition of performance level, and section limit state. Fiber model, lumped plasticity model, multi-spring model, and finite element model can accurately simulate the behavior of self-centering shear wall, but there are some differences in parameter sensitivity.Thus, some current research challenges and prospects were presented to provide theoretical and technical support for the development and application of self-centering shear wall structure system: the elastic and inelastic behavior of prestressing tendon which can cause prestress loss and insufficient deformation capacity during rocking, the connection performance between self-centering shear wall and adjacent structural components such as the floor system and its influence on self-centering ability, collapse control with the failure of post-tensioning tendon and dissipating device, and utilization of multiple dissipating rocking interfaces between wall panels to mitigate higher mode effects and estimation of residual drift.