(同济大学土木工程学院  上海 200092)
【提要】采用有限元方法分析了火灾下约束钢梁随温度升高时的反应并与已有的试验结果进行了验证。进一步分析了梁的轴向约束、梁端转动约束以及荷载比对约束钢梁受力性能的影响。总结了约束钢梁在火灾下的变形及轴力的发展规律。最后提出了约束钢梁的实用抗火设计方法，可供结构抗火设计时参考。
【关键词】  钢结构  约束钢梁  抗火设计  悬链线效应
Behavior of Restrained Steel Beams Subjected to Fire and Practical Fireresistant Design Method/Guo Shixiong,Li Guoqiang(Dept.of Structural Engineering,Tongji University,Shanghai 200092,China)
Abstract:The behaviour of restrained steel beams subjected to fire is analysed with FEM and verified by experimental results.The effects of axial restraint,rotational restraint and load ratio of the beam are discussed.The development of the deflection and axial force of the restrained beam subjected to increasing temperature is summarized and a practical fireresistant design method for restrained beam is presented.
Keywords:fireresistance;steel structure;catenary action;ultralarge deflection