【摘要】 针对"5.12"汶川大地震中大多数钢筋混凝土框架结构出现了大量的柱铰破坏机制而不是梁铰破坏机制的问题,2010版抗震规范提高了框架结构强柱弱梁的柱端弯矩增大系数。对于常见的由钢管混凝土柱和钢-混凝土组合梁组成的组合框架结构,规范中没有给出相应的方法来实现强柱弱梁。根据组合框架的受力特点,采用Pushover分析方法,对组合梁-方钢管混凝土柱框架结构的破坏模式进行研究,讨论了柱和梁极限弯矩比与梁柱线刚度比对结构屈服机制的影响;结果表明,采用RC框架弹性内力调整的方法,不足以真正实现强柱弱梁的屈服机制。并初步建议了实现组合梁-钢管混凝土框架结构强柱弱梁的设计公式,为组合框架结构的设计提供参考。更多还原

【Abstract】 In order to solve the problem that for general composite frame consisting of concrete-filled steel tubular(CFT) columns and steel-concrete composite beams(CB),the method to achieve strong column-weak beam behavior is not available in China code,GB 50011—2010,Pushover method was applied to study the damage mechanism of the CB-concrete-filled square steel tubular(CFST) column frame.The influence of ultimate moment ratio(column to beam) and beam-column line stiffness ratio on the structural yield mechanism was discussed.The analysis results showed that the method by adjusting the elastic inner force for RC frame can not give a guarantee to fulfill the strong column-weak beam yield mechanism.Furthermore the design formula to make sure the strong column-weak beam mechanism of CB-CFT column frames was preliminarily suggested,which could offer some valuable references in design of composite frame structures.更多还原