钢筋混凝土框架结构火灾反应全过程数值分析  

Numerical Simulation of Reinforced Concrete Frame Structure in Fires

作　　者：刘永军[1] 毕然[1] 腾飞[2] 刘洋洋[1] 

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168 [2]辽宁省建设科学研究院,辽宁沈阳110005

出　　处：《沈阳建筑大学学报（自然科学版）》2013年第3期405-411,共7页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家十二五科技支撑计划项目(2012BAJ11B02)

摘　　要：目的从火灾场景的模拟、构件内温度场和结构的变形反应三个方面对钢筋混凝土框架结构的火灾全过程进行研究,为抗火设计提供参考.方法采用火灾模拟软件FDS对某商场首层火灾进行模拟,并对火灾下温度分布过程进行了研究,在此基础上利用ANSYS有限元分析软件对火灾条件下的构件进行温度场分析和变形分析.结果边柱、中柱以及节点处温度靠近构件截面内部温度逐渐降低,且升温速率趋于缓慢.节点核心区的温度较周围的梁段和柱段偏低.各跨中挠度达到耐火极限的时间满足规范要求,结构各构件相继失去承载能力而发生倒塌.结论火灾模拟软件FDS得到的实际火灾升温曲线与国际标准火灾升温曲线相比温度偏低,采用国际标准升温曲线进行结构分析是偏于保守的,因此笔者建议将FDS对火灾的模拟结果作为结构分析的依据.In this paper, the whole numercial simulation process, including fire scenarios in a building, tem- perature distribution in structural members, and structural deformation, is studied using software to provide a reference for fire resistant design. The fire simulation software FDS is used to simulate fire on the first floor of a four story shopping mall, and the temperature distribution process is studied, on the basis of that, using the finite element analysis software ANSYS to analyze temperature and deformation of members under fire. The actual heating curve of the mall in fire is got, side column and middle column, beam and node cross-sec- tion temperature field distribution, the midpoint of the different position of the bottom edge of the column cross -section of time-temperature curves, the framework of temperature field contours and structural deforma- tion maps are also achieved. Fire simulation software FDS actual fire temperature curve with international standards of fire heating curve compared to the low temperature side column, the column and the node at temperatures close to the member section internal temperature is gradually reduced, and the heating rate tends to be slow. Temperature in the core area of joint are low compared to that around the beam and column seg- ment. Span deflection reached the time of the fire resistance to meet the specification requirements, the struc- ture of each member after another collapses loss of carrying capacity.

关 键 词：混凝土框架结构 火灾模拟 有限元模型 耐火极限 

分 类 号：TU375.4[建筑科学—结构工程]