钢筋混凝土框架结构层间弹塑性位移计算方法及试验研究

钢筋混凝土框架结构的层间弹塑性位移是判别结构倒塌极限状态的重要指标,目前我国抗震规范规定的弹塑性位移限值仍是基于构件试验研究的结果,缺乏结构层面的计算方法和试验验证.为此,将规则框架结构的层间位移等效为梁柱组合体的侧移变形,分析组合体变形的组成,建立了梁柱组合体变形与构件变形的转换方法,提出了"强柱弱梁"型框架结构层间...

Calculation method and experimental study of elasto-plastic inter-story drift of reinforced concrete frame structures

The elasto-plastic inter-story drift of reinforced concrete frame structures is an important criterion for checking whether a building collapses under rare earthquake.At present,the elastoplastic deformation limits specified in Chinese seismic code are obtained from relevant tests on structural members,without considering the overall system behavior,nor supported by the system-level tests.In this paper,the inter-story drift of frame structures was converted to the deformation of beam-column sub-assemblages.The deformation constitution of the sub-assemblages was analyzed.The transformation methods between the deformation of the sub-assemblages and members were established.The calculation methods of the inter-story drift angle and the overall lateral drift of the frame structures with‘strong column and weak beam’mechanism were proposed,with considering the deformation properties of frame structures.Three reinforced concrete frame structures were tested,the inter-story drift angle of the frame structures and the development of the relationship between the deformation of members and sub-assemblages were analyzed.The calculation methods were verified.The results show that the deformation contributed by the beams is greatly affected by the axial compression ratio at the initial stage of loading.The beam deformation decreases with the increase of axial compression ratio.The deformation contributed by the joints(about 0.9%)is negligible under a small axial compression ratio.The axial compression ratio and beam column linear stiffness ratio have little influence on the deformation constitution of the sub-assemblages for the frame structures with‘strong column and weak beam’mechanism.The calculation results of the inter-story drift angle and the overall lateral drift of the frame structures with“strong column and weak beam”mechanism show good agreement with the test results.