预制装配自复位摇摆桥梁结构体系抗震机理与性能设计方法

High energy-consumption in construction process and hard to rehabilitate as a result of seismic ductility design of current bridge structures are outstanding problems to be resolved, the novel bridge structural system with features of efficient construction, controllable seismic damage and quick earthquake resilience should be urgently developed. On the basis of previous seismic performance research of self-centering bridge columns, this proposal is initiated to propose and develop a precast assembled self-centering rocking bridge structure system. A series of shaking table tests utilizing shaking table array for overall self-centering rocking bridge models, quasi-static cyclic loading tests for crucial sub-assemblage and additional energy dissipaters, and theoretical analyses and refine numerical modeling for self-centering rocking bridge structural systems are conducted and performed as technical measures. Focusing on key issues of seismic resistance mechanism and performance-based design method, this project mainly investigates reasonable connection configurations, mechanical performance, rocking behavior, local damage evolution, energy dissipation mechanism, failure mode, and earthquake resilience evaluation methodology of the proposed self-centering rocking bridge structural system. Self-centering, rocking and energy dissipation mechanisms are revealed and self-centering capacity evaluation method is established for the novel bridge structural system. Performance level and performance indexes for earthquake resilient self-centering rocking bridge structural system will be proposed, and two-stage performance-based design methodology is preliminary presented. The implementation of this project will provide theoretical principle and scientific evidence for seismic design guidelines and engineering practice of self-centering rocking bridge structural system.

为解决当前桥梁结构建造的高能耗和延性抗震设计造成的震后难以修复等突出问题，亟待发展可高效建造、地震损伤可控、震后可快速恢复功能的桥梁抗震结构体系。本项目拟在前期自复位桥墩抗震性能研究基础上，提出并发展预制装配自复位摇摆桥梁结构体系，通过整体结构模型多子台振动台试验、关键构件及附加耗能部件的拟静力试验、结构体系的理论分析和精细化数值模拟等技术手段，聚焦自复位摇摆桥梁结构体系的抗震机理和性能化设计方法等关键问题，重点研究自复位摇摆桥梁结构体系的关键连接构造、受力性能、摇摆行为、局部损伤演化及耗能机理、失效模式和震后可恢复能力评估等内容。揭示该类桥梁结构体系的自复位、摇摆和耗能等抗震机理，建立其震后自复位能力评价方法。提出震后可恢复功能自复位摇摆桥梁结构体系的性能水准和性能目标，初步建立两阶段性能化实用设计方法。研究成果可为自复位摇摆桥梁结构体系抗震设计规范和工程应用提供理论基础和科学依据。

本项目在前期自复位桥墩抗震性能研究基础上，提出并发展了预制装配自复位摇摆新型桥墩以及桥梁结构新体系，通过桥墩以及整体结构模型试验、关键构件及附加耗能部件的拟静力试验、结构体系的理论分析和精细化数值模拟等技术手段，聚焦自复位摇摆桥墩和桥梁结构体系的抗震机理和性能化设计方法等关键问题，研发了U形钢板耗能装置及三角形钢挡块等装置以提高桥梁的抗震韧性。项目重点研究了自复位摇摆桥墩及桥梁结构体系的关键连接构造、受力性能、摇摆行为、局部损伤演化及耗能机理、失效模式和震后可恢复能力评估等内容。揭示了新型自复位桥墩及桥梁结构体系的自复位、摇摆和耗能等抗震机理，提出了基于极限偏移率和残余偏移率双参数的桥梁抗震韧性评价方法，初步建立了基于一致屈服位移和极限位移的自复位桥墩和桥梁抗震设计方法。研究成果可为自复位摇摆桥梁结构体系抗震设计规范和工程应用提供理论基础和科学依据。