该文以钢筋混凝土低延性框架结构为分析对象,总结该类结构及相关构件数值分析研究现状;基于桁架模型研究柱及节点组合体等关键构件的精细模型化思路与方法,并分别采用试验予以验证;以此为基础,借助在Open Sees软件中开发的数值子结构方法及平台,以汶川地震中严重受损的多层钢筋混凝土框架结构为对象建立精细化数值子结构模型,通过局部构件的精细分析研究其在强震作用下的抗震性能及失效模式。经该文研究表明采用桁架模型建立易于发生脆性破坏的柱及节点组合体等关键构件的精细化模型合理且准确;选择数值稳定且更适用的精细化模型与数值子结构平台分析涉及不同类型且易发生脆性破坏的低延性结构更具优势;针对低延性框架,不宜采用位移角限值作为结构性能评估的唯一判断依据,在分析中需考虑未达到目标位移前结构可能发生的脆性破坏模式。This paper firstly provides a short summary on the current research status on the numerical studying of low-ductility reinforced concrete （RC） frames and their related components, such as columns and joint subassemblages. Then detailed numerical modeling approaches of these key components using a truss model are provided and evaluated using several experiments. Finally, a numerical substructure method （NSM） developed in OpenSees is employed to build the detailed substructure model for analyzing a damaged RC frame subjected to Wenchuan Earthquake, and its aseismic performance and failure mode are studied in a detailed way according to the local performance. This study indicates that： the truss model performs well in simulating the nonlinear behaviors of columns and joints, especially to predict the brittle failures; numerical substructure method has great advantages, such as good numerical stability and applicable refined models, to study the performance of low-ductility RC structures; from the analytical results ofdarnaged RC frame, it can be found that displacement or inter-story drift should not be the only criterion to evaluate the low-ductility structures, and instead the possible brittle failures must be considered in the aseismic analysis.国家自然科学基金项目（51261120376,91315301-12
