基于残余位移的空间结构火灾温度场推定方法

Inverse presumption method for temperature fields of spatial structure based on residual displacement

针对火灾下结构温度场的反演问题,提出基于火灾后结构残余位移的温度场逆向推定方法,以有限元位移解与实测位移的差值为优化目标函数,选取合适的权函数构造火灾后的结构温度场逆向推定算法,通过温度场迭代计算定量得到结构经历的最高温度场分布,为科学评估火灾后的钢结构残余性能和结构修复加固提供理论依据.设计Williams双杆火灾试验,对比试验数据和逆向推定结果表明,温度场逆向推定方法是可行的,具有较高的精度.

A temperature inversion presumption method was developed based on post-fire structure residual deformations according to the inverse problem for temperature field of spatial structure exposed to fire.The difference between measured and finite element method values was made as optimization object function.An inverse algorithm was constructed by selecting an eligible weight function.The temperature field distribution was obtained by iterative calculation.A theoretical basis for scientificly evaluating the residual performances of post-fire structure and formulating reliable repair and reinforcement schemes was provided.Williams toggle frames for fire experiment were designed.The collected test data was compared with the presumption results.The method is feasible and the results have enough accuracy.