考虑材料在不同温度下的热力学性能变化，结合热弹塑性有限元与弧长法，研究加筋板在不同受热模式下的高温失效特性以及单轴压缩剩余极限强度.数值分析结果表明：迎筋面受热模式较背筋面受热模式升温更快，更为危险；背筋面受热模式下，结构易发生梁柱型失效；迎筋面受热模式下，结构失效表现为整体屈曲和筋的侧倾两种失效模式的叠加；当升温时间为140s时，背筋面受热和迎筋面受热模式下的结构单轴压缩剩余极限强度分别衰减至常温的13%和5%.
Considering the thermodynamic properties of materials at different temperatures, the method of thermal-elastic-plastic finite element analysis and riks method are used to study the collapse mode and residual ultimate strength of stiffened panel exposed to fire. The residual ultimate strength of the uniaxial compression at different heating-up time is also calculated. The numerical results show that：the whole structure heats up faster and fails earlier when stiffener heated, which is more dangerous. The collapse mode is beam-column type collapse when plate heated. And the collapse mode is a combine of overall collapse mode and local buckling mode of stiffener web when stiffener heated. The ultimate strength of plate heated stiffened panel reduces to 13% of that in normal temperature and the ultimate strength of stiffener heated stiffened panel reduces to 5% when the heating time reaches 140s.
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