轻钢活动房结构抗火性能分析

Fire resistance performance of mobile house

摘要:

为了得到轻钢活动房结构的抗火性能,采用理论推导和有限元分析相结合的方法对其进行研究．首先,从活动房单榀框架出发,基于临界温度相等的原则,将结构变形曲线简化为弹性段和垂直段,来代替原有的弹塑性模型;然后推导得到弹性段的变形公式,给出了分界点的确定方法,进而求得单榀结构火灾下的临界温度计算公式;最后,通过有限元比较了单榀框架和整体结构的抗火性能,并分析了框架榀数和着火位置对结构抗火性能的影响．分析结果表明:整体结构的抗火性能与单榀结构相近,框架榀数对整体抗火性能影响不大,最不利的火灾位置为中部房间．

Abstract:

Theoretical derivation and finite element method were developed in this paper to study the fire resistance performance of mobile house. First, based on the equivalent principle of the critical temperature,the structural deformation curve was simplified as elastic and vertical segments instead of the original elastic-plastic model. Then, deformation formula of the elastic segment was obtained by theoretical derivation, and the method of determining the dividing point was also provided. To this end, the critical temperature formula of frame under fire was obtained. Finally, the fire resistant performance of the entirety house structure and the single frame were analyzed and compared through finite element method. It shows that, the fire resistance performance of the entirety house structure is similar to single frame structure, the number of frame have little effect on the fire resistant performance of entirety house, and the most unfavorable fire location is the middle room.