【作者】 黄思凝；

【导师】 郭迅；

【作者基本信息】 中国地震局工程力学研究所 ， 结构工程， 2012， 博士

【摘要】 钢筋混凝土(RC)框架结构因具有施工简单、传力路径清晰和建筑平面布置灵活等优点，在现有建筑结构中占很大比例。然而汶川地震中极震区大量RC框架倒塌，造成重大人员伤亡。如何使RC框架结构具有更好的抗震能力，特别是抗倒塌能力，将是未来很长一段时间内结构抗震研究的主要目标。鉴于此，本文围绕RC框架地震损伤与倒塌问题，开展了系列模型结构地震模拟实验研究。首先量化了填充墙在框架抗震中的影响，对比了框架节点梁筋锚固不足的影响，分析了外廊式框架地震破坏及倒塌机理，导出了框架地震倒塌的临界方程。论文主要工作如下：1、通过振动台实验研究了RC框架中填充墙破坏状态对框架地震响应的影响。总结了结构基频率随地震动强度增加的变化规律；根据基频衰减程度，结合结构对应破坏状态，划分了填充墙所处的破坏阶段，确定了填充墙各破坏阶段的层间位移角限值。2、分别设计建造了节点梁筋标准锚固及锚固不足的框架模型进行地震模拟对比实验，根据对两模型节点破坏位置和节点区裂缝发展及分布模式，总结了节点传力路径和破坏机理，分析了节点梁筋锚固不足对整体结构屈服机制的影响。3、以漩口中学教学楼为例，对其倒塌模式做了细致的刻画，比较了其与附近未倒塌结构构造的差异，对这一典型外廊式框架结构的倒塌原因做出初步判断。4、为了再现漩口中学教学楼倒塌过程，取其中两榀代表性框架，按1/4比例设计建造了模型并进行振动台试验。通过对试验过程的详细分析认识到，非廊侧柱动轴压比过大，延性显著降低，柱端塑性铰区表面混凝土剥落、核心混凝土压碎、柱上节点在强大重力作用下下坐进而倒塌。5、通过对模型中柱受力的定量分析，建立了框架平衡方程，得到模型中柱底层临近倒塌时刻的最大水平变形量，推导了模型结构基于最大位移量理论的倒塌临界方程。将应用临界方程求得的中柱最大位移结果与实验结果相对比，验证了临界方程的可行性。更多还原

【Abstract】 Due to its simplicity of construction, clear force-transferring path and goodflexibility in architectural planning，reinforced concrete frame structure is a majorstructural type in our society. However there were a great number this kind ofstructures collapsed and killed numerous people in meizoseismal area during theMay12,2008Wenchuan earthquake. It is a great challenge for structuralengineers to improve the seismic performance, especially collapse resistantcapability of RC frame structures. The author focuses on earthquake damage andcollapse of RC frame structure, conducts comprehensive shaking table tests onRC structural models. The effects of infill walls and anchor pattern of beamreinforcement at joint area are tested; damage and collapse mechanism of RCframe with external corridor is summarized; critical equilibrium equation whichdescribes collapse status of RC frame is derived. Contents and conclusions can besummarized as:1. Effects of infilled walls on earthquake response of RC frame structurewere experimentally investigated. The relationship between fundamentalfrequency and PGA was summarized. The damage extent of infilled wall wasscaled into four levels according to the value of the fundamental frequency andthe corresponding story drift of each level was determined.2. Scaled models with standard joints and insufficient anchor joints weretested respectively by shaking table. Effects on failure mechanism of differentanchor methods were discussed.3. The collapse status of Xuankou Middle Scholl building which is a typicalRC frame structure with external corridor was investigated in detail, itsdifferences with adjacent other buildings were analyzed. Preliminary analysis onthe collapse reason was presented.4. In order to verify the above analysis, scaled model of the Xuankou MiddleSchool building was tested by shaking table. Experiment and analysis showedthat the over high dynamic ratio of axial force to strength at columns other thancorridor badly decreased the ductility of these columns, and collapse initializedthis side.5. Based on analysis of the load-carrying capacity of the intermediatecolumns, equation which describe the critical stability of the RC frame structurewere established, corresponding story drift limits were derived.更多还原