基于性能的既有钢筋混凝土结构抗震评估方法与应用

Performance-based seismic evaluation method and application for existing reinforced concrete structures

第五代《中国地震动参数区划图》颁布实施以后,抗震设防要求全面提高,抗震评估和加固工作也遇到了越来越复杂的挑战。引入基于性能的抗震设计原理,提出基于性能的既有结构抗震评估方法,介绍了方法体系中地震作用取值、抗震性能目标、耐久性损伤模型和抗震分析方法等内容,并以一框架结构教学楼加固项目为例,说明了基于性能的抗震评估与加固设计的可行性。研究结果表明:对于一般既有建筑,应根据等超越概率原则来调整其地震作用;既有建筑抗震设防目标在相同概率保证的前提下与新建建筑保持一致,因此其抗震性能目标可参照新建建筑的相关规定确定;既有结构的性能评估应考虑其耐久性损伤;基于性能的既有建筑抗震评估方法,能直接定量评估建筑结构在中震和大震下的性能,因此可更准确判断既有建筑是否需要抗震加固及如何更有效地加固结构。

After the promulgation and implementation of the fifth-generation Seismic Ground Motion Parameters Zonation Map of China, seismic fortification requirements are up comprehensively. Seismic assessment, as well as seismic reinforcement, has more and more complex challenges. By introducing performance-based seismic design principle, a performance-based seismic assessment method for existing buildings is proposed. The value of seismic action, seismic performance target, durability damage model and seismic analysis method in the evaluation method system are introduced. An example of frame structure teaching building reinforcement project can illustrate the feasibility of performance-based seismic assessment and reinforcement design. The research results show that the earthquake action should be adjusted according to the principle of equal exceedance probability for the existing buildings, and the seismic fortification targets of existing buildings are consistent with those of new buildings under the premise of the same probability guarantee. So the seismic performance targets of existing buildings can be determined by the relevant regulations of new buildings. At the same time, the durability damage of existing structures should be considered in the performance evaluation. The performance-based assessment and design method for seismic reinforcement of existing buildings can directly and quantitatively evaluate the performance of building structures under medium and large earthquakes, for more accurate judgement in existing buildings reinforcement.