建筑结构遭受火灾时的初期,由于构件内部温度较低,对材料性能影响较小,结构的破坏形态,一般不可能趋向于脆性破坏;但当火灾燃烧时间较长时,构件内部温度升高较大,则对材料性能影响较大,除产生较大变形外,并产生应方重分布,其破坏形态一 When the building structure is exposed to fire at the beginning of the fire, due to the low internal temperature of the components, the impact on the material properties is relatively small, and the structural damage pattern is generally not likely to tend to brittle failure; however, when the fire burning time is long, the internal temperature of the components increases. Larger, it will have a greater impact on the material properties, in addition to generating a large deformation, and resulting in the redistribution of the square, its destruction of a