中文摘要：

本文采用数值方法对某大型体育馆的特定火灾场景进行模拟计算，对由于火灾导致的温度分布和结构破坏过程进行数值模拟．分析结果表明体育馆在火灾下随着温度上升，材料的弹性模量降低，结构刚度变小，顶部首先发生大变形，同时强度的降低和支撑能力削弱导致结构在重力等恒载作用下迅速发生破坏．破坏形式为屋顶钢网架在高温下发生大变形导致屋顶的整体塌落．这一结果对体育馆的消防设计和火灾应急安全具有重要的指导意义．

英文摘要：

Numerical simulations of fire disaster in a specific gymnasium were performed and the temperature distribution and the structure failure process induced by fire were investigated. The results showed that the elastic modulus of steel material dropped quickly with the increasing of temperature caused by fire. This would lead to the weakening of the stiffness of the structure. Large deformations of steel structure develop first at the coping, and then the structure failure occurs rapidly under the gravity loading after the reduction of strength and the losing of supporting resistance. The final failure pattern of the structure was the global collapse of the steel grid roof by the large deformation due to the fire induced high temperature. These research results may provide important message for the fire control design and emergency response of gymnasiums.