喷水急冷作用下火灾高温钢框架损伤过程的简化分析方法

Simplified analysis method for the damage of high temperature steel frame rapidly cooled by spray water in fire

针对低温喷淋水作用下高温钢结构急速冷却产生的冲击效应,建立了弹簧-梁柱的简化分析三折线模拟弹簧模型以及基于能量平衡的简化分析方法,钢框架结构在喷水冷却过程中其屈曲前的变形不大,比受热升温过程中的要小很多,但结构局部的最大轴力要比受热升温过程中的大很多,能够达到升温过程中的4.5倍以上。同时,将相关的计算结果与模拟结果进行比较,二者的结果非常接近,结果相差在2.6%以内,完全可以满足相关工程计算精度的技术要求。本简化计算方法可以用于分析和评估火灾高温钢框架在喷淋水快速冷却下结构的损伤和破坏程度。

For the impact effect of rapid cooling by spray water at low temperature on high temperature steel frame structure,a three-broken-line simulation model and simplified analysis method based on energy balance for spring-beams and columns was set up. Deformation of steel frame structure,before buckling in water spray cooling process was not large,it was much smaller than that produced in heating-up,but its local maximum axial force was much larger than that produced during heating-up,their difference could reach more than 4. 5 times. The related calculation and simulation results were analyzed and compared,they were very close to each other,their average difference were below 2%,the simplified analysis method could completely meet the precision requirement of engineering calculation,it was useful to analyze and evaluate the damage and destruction of high temperature steel frame structure rapidly cooled by spray water.