基于地震损失风险的多层砌体结构抗震构造措施评估

Evaluation of seismic structural measures of multi-storey masonry structures based on seismic loss risk

地震损失风险可反映建筑结构的抗震性能,其定量评价不仅是结构抗震设计参数选择的重要环节,也是防震减灾决策的重要依据。为研究采用不同抗震构造措施的砌体结构的抗震能力,提出了砌体结构基于地震危险性和结构易损性的损失评估方法。设计了25种不同抗震构造措施的砌体结构模型,采用非迭代静力分析的砌体结构易损性分析方法研究了地震作用下砌体结构的失效概率,并分析了砌体结构在1年和50年内可能发生的经济损失和人员伤亡损失风险。结果表明,抗震构造措施可显著降低砌体结构地震损失风险,无抗震构造措施的砌体结构倒塌概率是采用完备抗震构造措施时的5.5倍。基于人员伤亡率控制的计算结果与现行设计规范要求基本一致,但对低层砌体结构的抗震构造措施要求更为宽松。

Seismic loss risk can reflect the seismic performance of building structures,and its quantitative evaluation is not only an important link in the selection of structural seismic design parameters,but also an important basis for earthquake prevention and disaster mitigation decisions.In order to evaluate the seismic capacity of masonry structures with different seismic structural measures,a method for calculating seismic loss based on sesmic risk and structural fragility was proposed.25 types of masonry structure models with different seismic measures were designed,and failure probability of masonry structures under earthquake action was studied by using non-iterative static analysis method for masonry structure fragility analysis.The annual and 50-year risk of economic loss and casualty loss that may occur in masonry structures were analyzed.The results indicate that the earthquake loss risk decreases with the increase of seismic measures,and the collapse probability of masonry structure without seismic structural measure is 5.5 times of that with sufficient seismic structural measure.The calculation results based on casualty rate control are basically consistent with the requirements of the current design code,but the requirements for seismic structural measures of low-rise masonry structures are more relaxed.