摘要
我国城乡地区存在大量缺乏规范抗震设计的中低层无筋砌体(URM)结构和钢筋混凝土(RC)框架结构,其抗震性能远未达到设防要求。既有区域震害模拟聚焦于城市中按规范设计的建筑结构,震害预测模型构建依赖于结构抗震规范设计流程及抗震性能参数统计结果,且未考虑结构在不同加载路径下承载力和刚度退化特征,难以适用于我国城乡缺乏规范抗震设计的中低层URM和RC框架建筑群的震害评估,尤其抗倒塌性能评估。为此,针对我国城乡中低层URM结构和RC框架结构,建立了适用于区域尺度建筑群地震倒塌分析的简化模型。首先,提出了关键细部建筑参数(材料参数、构件尺寸和构件数量)预测方法,充分考虑关键宏观建筑参数(建造年代、建造地区、外观布局)的影响,实现根据易获取的关键宏观建筑参数直接推断细部建筑参数取值。其次,引入区分模拟单调和循环加载路径承载力退化特征的构件恢复力模型,建立结构等效单自由度模型,满足结构倒塌分析中合理模拟承载力退化特征的需求。考虑区域建筑数量庞大,给出了结构等效单自由度模型参数简化求解方法,可以避免对结构进行精细化建模和繁琐的非线性分析。最后,通过URM结构和RC框架结构算例分析表明,相比于精细化模型,简化模型对结构倒塌时地震动强度和顶点位移角的计算误差均小于15%,验证了所提出模型在抗倒塌性能评估中的可靠性。
Numerous low-to mid-rise unreinforced masonry(URM)structures and reinforced concrete(RC)frame structures in China's urban and rural regions were constructed without adherence to standardized seismic design codes,resulting in seismic performance that fails to meet mandated fortification requirements.Current regional seismic damage simulations predominantly target code-conforming urban structures.Their regional seismic damage prediction models are based on prescribed seismic design codes and statistical parameters of seismic performance,,lacking consideration of strength/stiffness degradation behaviors under varying loading paths.Therefore,these models have poor applicability in regional seismic damage evaluation of low-to mid-rise URM and RC frame structures in urban and rural regions,particularly for seismic collapse performance evaluation.This paper established a simplified model for regional-scale seismic collapse analysis of low-to mid-rise URM and RC frame structures in urban and rural regions.Firstly,a predictive method for key building parameters(material property parameters,member dimensions,and component quantities)was proposed,which systematically accounted for the influence ofcritical macro-level building parameters(construction age,location,and layout),thereby effectively enabling the direct derivation of detailed building parameters from easily obtainable macro-level characteristics.Secondly,an equivalent single degree of freedom(ESDOF)model was established using the structural component hysteretic model that clearly distinguishes bearing capacity degradation behaviors under monotonic and cyclic loading paths,ensuring reasonable simulations of degradation behaviors in collapse analysis.Furthermore,given the extensive number of regional structures,a simplified parameter determination method for the ESDOF model was developed to circumvent the need for detailed numerical modeling and intricate nonlinear pushover analysis.Finally,numerical cases of both URM and RC frame structure were conducted.The results show that the computational errors of the simplified model for both seismic intensity and roof drift ratio at collapse are consistently below 15%compared to the refined model,demonstrating the high reliability of the proposed simplified model in seismic collapse performance evaluation.
作者
余丽玲
董志骞
李钢
黎莉
秦敢
YU Liling;DONG Zhiqian;LI Gang;LI Li;QIN Gan(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116033,China;School of Safety Engineering,China University of Mining and Technology,Xuzhou 221006,China;Shenzhen Technology Institute of Urban Public Safety,Shenzhen 518001,China)
出处
《建筑结构学报》
北大核心
2025年第11期1-21,共21页
Journal of Building Structures
基金
国家自然科学基金项目(52225804)。
关键词
无筋砌体结构
钢筋混凝土框架结构
区域震害模拟
建筑参数预测
倒塌分析模型
参数确定简化方法
unreinforced masonry structure
reinforced concrete frame structure
regional seismic damage simulation
building parameter prediction
collapse analysis model
simplified method of parameter determination
