服役砌体结构建筑抗震可靠性向量及加固分析

Seismic Reliability Vector and Strengthenging Analysis of Existing Masonry Structure

根据具有中介状态结构可靠性向量理论,认为砌体结构具有"安全-中介-失效"三级工作模式,这里的"中介"即为砌体结构带"故障"工作状态,砌体结构处于3种工作模式的概率组成可靠性向量。基于工程结构全寿命期抗力退化模型,提出了一种适合评价现役砌体结构抗震性能的时变可靠性向量分析方法。以砌体抗剪强度为指标,分别建立了砌体结构的三层次时变可靠性向量计算模型,同时给出了加固砌体结构时变可靠性向量计算的一般方法。文中运用时变可靠性向量分析方法,分析了一栋4层砌体结构,得到了原结构与加固结构墙体、楼层、结构体系三层次可靠性向量,并进行了对比分析。可为砌体结构的抗震性能评价和加固设计提供理论依据。

According to the theory of reliability vector of structure with intermediate state, it is assumed that masonry structure has three-stage work modes of safety, intermediate and failure. The intermediate state means when the structure works with trouble, and reliability vector is composed of the probability of being in each state. A time-dependent reliability vector analysis method is proposed for assessing seismic performance of existing masonry structure based on resistance deterioration model of engineering structure in life- cycle. With masonry shear for index, model of three levels of time-dependent reliability vector is put forward respectively to calculation the reliability vector of walls, stories and structures system of original structure and strengthened structure. This method is used to analyze a masonry structure with four stories, and the reliability vector of the wails, stories and structure system is calculated. In addition, reliability vectors are developed for the strengthened structure based on a specific retrofit technique. Finally, all the reliability vectors are compared with each other, which can provide theoretical basis for assessment of seismic performance and strengthening design.