考虑多重不确定性的我国多层#br# 冷成型钢结构地震风险评估

准确评估建筑结构的地震风险是实现其性能化抗震设计的重要组成部分。冷成型钢结构体系作为绿色和工业化建筑的典型代表，却鲜有针对于我国的地震风险评估研究。文章旨在分析和评估多层冷成型钢结构抗震分析所涉及的多重不确定性因素，进而定量评估该类结构在我国的地震风险。文章设计1栋八度抗震设防的6层冷成型钢结构，基于经过振动台验证的简化数值分析方法建立结构的简化数值模型，定量求解结构的多重不确定性因素和在使用周期内(50年)的地震风险。研究结果表明：由于我国一些地区的地震危险性形状系数较大，在考虑多重不确定性后，结构的破坏概率显著提高，50年使用周期内倒塌概率的增幅达到10倍以上；算例结构在50年使用周期内基本满足“小震不坏、中震可修、大震不倒”的抗震设防要求，对于个别特殊区域应适当控制结构发生轻微破坏的概率。此外，文章建议应全面考虑多重不确定对冷成型钢结构地震风险的影响，对不确定性参数的取值和地震风险的计算方法可提供借鉴。

Seismic risk assessment of mid-rise cold-formed steel structures in China#br# considering various uncertainties

Seismic risk assessment is an important aspect for the performance-based seismic design of building structures. Cold-formed steel (CFS) structure is a typical green and industrialized building system, but very few investigations have been conducted on seismic risk assessment of CFS structures. This study aims at analyzing and assessing various uncertainties involved in seismic analysis of CFS structure, and then quantifies its seismic risks. A typical 6-story CFS building of eight-fortification is designed. Based on the simplified numerical analysis method verified by shaking table tests, a simplified numerical model of the building is established for quantifying various uncertainties and seismic risks. The results show that: because the shape parameters of seismic hazard function are large for some regions in China, the failure probability of CFS structure increases remarkably if various uncertainties are considered, and the collapse probability in 50 years of the building increases more than ten times; the case building basically meets the requirements that “no damage under minor earthquake, no un repaired damage under moderate earthquake, and no collapse under major earthquake” proposed by the standard in China, but the probabilities on slight damages of the CFS buildings at some special regions should be controlled appropriately. Besides, various uncertainties shall be considered comprehensively for their effects on seismic risk quantification of CFS structures, and the values of uncertain parameters as well as the method of calculating the seismic risks proposed in this study can be referred to.