高层钢筋混凝土框架结构耐火性能分析

Fire performance analysis of high-rise reinforced concrete frame structures

本文建立了火灾下高层钢筋混凝土框架结构的有限元计算模型,研究了高温下框架结构的变形规律、结构的破坏机制、塑性铰分布规律、受火梁的内力以及耐火极限。分析表明,本文高层钢筋混凝土框架结构火灾下发生了框架局部破坏和框架整体倒塌两种破坏形态;框架局部破坏情况下,当发生破坏的框架梁位于框架高度中间时,框架的耐火极限较大,当发生破坏的框架梁位于框架顶部或底部时,框架的耐火极限较小。

A finite element model of high-rise reinforced concrete frame structure in fire is established Deformation and failure mechanism, distribution of plastic hinges, redistribution of the internal forces and fire resistance are analyzed. The results show that the frame structure presents two failure modes, which are the local frame failure and the overall frame collapse failure. Under the local frame failure mode, the fire resistance is larger when the fire locates in the middle part of the frame structure and is smaller when the fire locates in the bottom and on the top of the frame structure.