基于耦合的系统方法在防火安全评估中的应用

以奥运场馆改造项目为背景,利用计算机技术,基于性能化防火分析的思想,采用自行开发的火灾安全模拟系统BFIRESAS,对奥运场馆的火灾安全性能进行了综合分析。该系统采用数值模拟的方法,将火灾场景模拟分析与结构分析综合为一体,模拟了北京工人体育馆在设定火灾下的火灾场景和结构温度场的分布,分析了其屋面钢结构体系在火灾作用下的结构反应和力学性能。分析结果显示:火灾影响下原有结构体系的平衡被打破,火灾下的结构破坏表现为整体性的破坏,因而需要进行全面的整体分析,而不能仅仅考虑局部的影响。对该场馆的火灾安全提出了进一步分析的建议。

Application of the BFIRESAS system on fire safety evaluation

According to the requirement of the fire safety analysis of gymnasiums for 2008 Beijing Olympic Games,the exited gymnasiums which were constructed in the past years should be evaluated for their safety.A newly developed integrated system-BFIRESAS was introduced to analyze the overall fire safety behavior of gymnasiums under fire conditions.This system adopts numerical simulation technology to execute the performance-based fire analysis ideas,and is able to perform the integrative process of fire safety analysis from fire simulation to structural analysis.One of the selected gymnasiums for the competition venues of 2008 Beijing Olympic Games-Beijing worker gymnasium,has been studied as a case by the BFIRESAS system.Through the BFIRESAS,several potential fires can be specified and the evolvement process of fire scenario could be simulated.Based on the variable temperature fields during the fire evolvement process,the steel structural respond and behavior of gymnasium in fire could be analyzed.Moreover,the critical temperature and critical time could be estimated.The results show that the structural respond and behavior of large space building under fire conditions have the systemic nature of a coherent whole,rather than the local effect.The case demonstrates that the BFIRESAS system is a powerful tool and has high advantage while used to perform fire safety analysis.