震损RC框架残余抗震性能评估理论与基于预制部件的快速加固方法研究

Previous major earthquakes have caused damage and destruction to a large number of buildings. The residual seismic performances and resilience assessment of the earthquake-damaged structures have become an urgent problem to be solved in the seismic research field. Precast buildings have become an important development direction in civil engineering. Retrofitting of earthquake-damaged structures based on precast components can significantly shorten the structural function recovery time and reduce the indirect economic loss. This project focuses on the reinforced concrete (RC) frames with earthquake damage. Based on the experimental and theoretical research on the residual mechanical capacities and seismic performances of the earthquake-damaged RC components, an assessment method of the residual seismic performances of the earthquake-damaged frames is established, and the resilience capacities of the earthquake-damaged frames are studied, in order to provide a scientific basis for retrofit design. Based on the principle of rapid retrofit, precast retrofit components are designed using the assembly concept. The mechanical properties and seismic performances of the precast component retrofitted earthquake-damaged RC components and frames are investigated, and the mechanism and failure modes of the precast component retrofitted earthquake-damaged frames are revealed. The seismic performances of the retrofitted earthquake-damaged frames during the re-service period is also studied based on the seismic hazard theory. Based on the principle of global optimization of the retrofit cost and seismic performance, a performance-based seismic design method is proposed for the precast component retrofitted earthquake-damaged frames. The research of this project will provide a scientific basis for the assessment of the residual seismic performances of earthquake-damaged frames, and also provide a new retrofit technology and design method for the rapid retrofit of earthquake-damaged frames.

历次大地震均造成大量建筑结构的损伤与破坏，震损结构残余抗震性能和可恢复评价已成为抗震领域亟待解决的问题。预制装配式建筑已成为土木领域的重要发展方向，基于预制部件对震损结构进行加固能显著缩短结构功能恢复时间，减少间接经济损失。本项目以震损钢筋混凝土框架为研究对象，通过震损构件残余力学性能及抗震性能的试验与理论研究，建立震损框架残余抗震性能评估方法，并研究震损框架的可恢复能力，为加固设计提供科学依据。基于快速加固原则，采用装配式理念设计预制加固部件，研究其加固震损构件、震损框架的力学性能与抗震性能，揭示预制部件加固震损框架的受力机理、地震破坏失效模式与机制，并开展基于地震危险性理论的加固震损框架后续服役期抗震性能研究。以加固成本和抗震性能整体最优为原则，提出震损框架基于性能的预制部件抗震加固设计方法。本项目的研究将为震损框架残余抗震性能评估提供科学依据，为其快速加固提供新的加固技术与设计方法。

本项目针对震损RC框架的剩余抗震性能以及基于预制部件的抗震加固问题开展了系统的研究，取得了如下研究成果：（1）通过大量试验数据的统计分析，获得了震损RC构件抗震性能随峰值位移的退化关系，提出了震损构件的骨架曲线模型，并提出了震损RC框架的高精度有限元建模方法。（2）提出了基于性能冗余率的震损结构剩余抗震性能评估方法，揭示了震损RC框架的剩余抗震性能；为能考虑地震动特征的影响，建立了基于地震能量的震损结构剩余抗震性能评估方法，与现有方法相比，该方法具有更高的计算效率，适合于建筑群的评估。（3）基于装配式理念，提出了震损构件的预制部件击鼓构造方法，开展了预制部件加固震损RC柱轴压力学性能试验，验证了预制部件加固方法的有效性，并揭示了其加固受力机理。（4）针对震损RC柱的抗震加固问题，提出了预制壳和预制部件两种加固震损RC柱的构造方法，通过抗震试验验证了加固方法的有效性，并揭示了其加固机理。（5）在预制部件加固修复的理念上，进一步提出了可修复组合柱构造方法，该柱具有低残余位移特征，可以在震后更换耗能部件实现快速修复，开展了抗震性能试验验证了其有效性并揭示了抗震受力机理。（6）基于能量平衡原理，提出了震损结构基于能量的加固设计方法，定量考虑了损伤对加固的不利影响，可为实际震损结构的加固修复提供参考。