中文摘要：

结合钢交错桁架结构的特点,提出了其在火灾高温作用下的三折线简化模型,并对高温作用下结构的侧移变化特征和高温引起的附加倾覆力矩进行了分析,给出了相应的理论表达式;结合有限元法,通过具体算例对该模型进行了验证。结果表明：侧移简化模型能较好地描述钢交错桁架结构在水平荷载和高温作用下的侧向变形情况;结构侧移和附加倾覆力矩计算方法简便可行,并具有较好的精度。

英文摘要：

A three-segment simplified model was presented for describing the lateral displacement of steel staggered-truss framing system subjected to high temperature according to the structural attributes.Both the structural lateral displacements and the additional overturning moment induced by high temperature were analyzed,and the corresponding calculation methods were proposed.Furthermore,associated with the finite element method,a case was given for clarifying the above method.Results show that the proposed simplified model can describe the lateral deformation of steel staggered-truss structure under lateral force and high temperature well.The calculation methods for the lateral displacement of structure and the additional overturning moment are relative simple,feasible,and have considerable precision.