新型性能可恢复摇摆结构基本力学行为及抗震设计理论

An innovative resilient rocking column(pier) with replaceable steel slit dampers was proposed and applied into a hybrid moment resisting frame to form an innovative resilient rocking structure. The fundamental mechanism and seismic design method of such structure will be studied. The following contents will be covered. (1) Steel slit dampers under different combination of external loads will be tested under pseudo-static loading protocol. The influence of different parameters on strength, stiffness and deformation performance of the dampers will then be studied and calculation method on the shear strength of specimens will be proposed. (2) Experimental research of the innovative resilient rocking columns(piers) under pseudo-static cyclic reversed loading will be carried out and the influence of different parameters on the load carrying capacity, stiffness, deformation capacity, hysteretic performance and resilient performance of specimens will be studied. (3) Full-scaled frames will be tested under pseudo-static reversed loading to investigate the influence of different parameters to the damage evolution, failure mechanism and overall seismic performance. The feasibility of the replaceable details of structures for restoring their original seismic performance will be validated. (4) Pseudo-dynamic test of full-scaled frames will be carried out to investigate the dynamic response patterns, dynamic characteristics and damage recovery ability of specimens under different earthquake levels. (5) Finite element models will be established and verified with test results and parameter analysis will then be carried out. Resilience based design method of the innovative resilient rocking structures will be proposed based on the experimental and numerical study. (6) Shaking table test of full scaled substructures will be carried out to study the dynamic response, dynamic characteristics and damage revolution patterns of the structures and reliability of the replaceable details and design methods of the structures were finally be validated.

提出一种带可替换开缝钢板阻尼器的新型性能可恢复摇摆柱(墩)技术，并应用于混合框架结构中，形成新型性能可恢复摇摆结构。围绕该新型结构的基本力学行为和抗震设计理论开展系统研究。主要包括：进行开缝钢板阻尼器在复杂受力状态下的拟静力加载试验，研究不同参数对试件强度、刚度和变形性能的影响，提出设计方法。进行摇摆柱拟静力抗震试验，研究不同参数对试件承载力、刚度、变形、滞回性能和性能恢复能力的影响。进行足尺框架模型拟静力抗震试验，研究不同参数对结构损伤发展、破坏形态和整体抗震性能的影响，验证可替换构造的合理性。进行足尺框架结构拟动力试验，研究不同地震水平下结构的地震反应规律、动力特性和灾损恢复性能等。采用试验验证的数值模型对结构或构件进行参数分析，并提出结构的可恢复性设计方法。进行足尺子结构模型振动台试验，研究结构在不同地震水平下的响应规律、动力特性、损伤发展规律，验证性能恢复的可靠性和设计方法可行性。

为实现地震后结构性能快速恢复，提出了新型性能可恢复摇摆柱(IRR柱)和带防屈曲盖板的震损可替换钢梁(RBRF梁)技术，围绕其受力机理、抗震性能和设计方法开展系统研究。主要开展的工作有：(1) 开展了22组足尺IRR柱的抗震性能试验，研究了轴压比、钢板阻尼器厚度、材料、形状、布置形式等参数对试件抗震性能的影响。结果表明，采用“强柱弱阻尼器”原则设计的IRR柱在水平荷载作用下，塑性变形均集中于可更换开缝钢板阻尼器上，IRR柱具有稳定的滞回耗能性能，水平承载力随轴压力和阻尼器厚度的增加而增加。 (2) 建立了IRR柱的精细化有限元模型，在试验验证基础上进行参数分析，揭示了IRR柱的受力机理,并提出了IRR柱的恢复力模型。研究结果表明：随着轴压比的增加，试件承载力增加，残余变形迅速减小，IRR柱滞回曲线由捏拢的“梭型”逐渐转变为“旗帜型”，表现出良好的可恢复性能。(3) 完成了 7 个可更换钢梁试件的抗震性能试验并开展了有限元参数分析。研究表明：设置防屈曲盖板的可更换钢梁试件，可更换翼缘连接板呈现出多波屈曲模式。可更换钢梁滞回曲线饱满，具有良好的塑性变形能力。基于试验研究和有限元分析，提出了震损可更换钢梁的荷载-位移恢复力模型。(4) 在前序研究的基础上，提出了新型功能可恢复钢框架(ERMR框架)，建立了ERMR框架的简化分析力学模型，并开展了结构的拟静力推覆分析，研究了不同设计参数下ERMR框架结构的损伤发展规律和性能变化。本项目研究成果可为震后功能可恢复结构的设计计算和工程应用提供科学依据。