罕遇和极罕遇地震作用下结构的一致风险抗倒塌设计方法研究

结合当前国际上以“抗倒塌”为目标进行地震动参数区划和以“一致倒塌风险”为设防目标进行结构抗震设计的最新发展趋势，针对目前我国第五代地震动参数区划图刚刚颁布但现行建筑抗震设计规范仍未进行修订的现状，拟以普通建筑结构（丙类建筑）和重要建筑结构（乙类建筑）为研究背景，研究适合我国建筑环境和地震环境的丙类建筑及乙类建筑倒塌风险可接受水平和条件倒塌概率可接受水平；提出极罕遇地震的新型定义，采用风险导向方法对罕遇地震和极罕遇地震的设防水准进行统一决策；研究基于场地地震危险性分析的风险导向目标反应谱构建方法以及基于目标反应谱的地震动记录选择、调幅和谱匹配方法；以钢筋混凝土结构为研究载体，研究罕遇地震和极罕遇地震作用下结构的一致风险抗倒塌设计方法。本项目研究成果可为进一步研究基于一致倒塌风险的结构多水准多阶段抗震设计方法和性能设计方法提供理论依据，为现行建筑抗震设计规范的修订提供决策支持。

Considering the newest trends of earthquake ground motion parameters zonation taking the collapse resistance as fortification target, and of seismic design of building structures based on uniform collapse risk; aiming at the existing status that the 5th-generation seismic ground motion parameters zonation map of China was just released but the current seismic deign code of buildings hasn’t been revised, in this project, the collapse resistant design methods of structures based on uniform collapse risk will be investigated. For this purpose, the acceptable levels of seismic collapse risk, as well as the acceptable levels of conditional collapse probability under rare and very rare earthquakes are made decision for both common and important buildings, which are suitable to Chinese building environment and seismic environment. A new concept of very rare earthquake is proposed, and the design levels of both rare and very rare earthquakes are unifiedly determined using the uniform collapse risk-targeted method. After that, the risk-targeted response spectra based on probabilistic seismic hazard analysis of sites are constructed, and the selection, scaling and spectrum-matching of ground motions based on the target response spectra are studied. Taking the reinforced concrete structures as research objects and case studies, four methods of collapse resistant design of structures based on uniform collapse risk are put forward. The research results of this project can provide the theoretical foundations for the further study on methods of multi-level and multi-stage seismic design as well as performance-based seismic design based on uniform collapse risk, and can also provide decision support for the revision of the current seismic design code of buildings.