高温下不同受火面对防屈曲支撑温度场的影响

At high temperatures,the fire face is affected by the anti-buckling support temperature field

采用数值模拟分析的方法,根据有限元分析软件Abaqus建立防屈曲支撑模型,然后采用温度场分析,利用ISO-834国际标准火灾升温曲线加载环境的温度,给出模型各部分材料的热工参数,定义约束、边界条件及部件之间的相互作用,通过热传导、热对流、热辐射的传热途径,分别考虑了一、二、三、四面受火,经过有限元分析计算后,得到防屈曲支撑整体以及各个部件的温度场分布规律。在受火60 min后,随着受火面的增加,跨中工作段的温度也逐渐增加,但是最高温度也只有70℃,在外侧的屈曲约束单元以及核心单元的连接段上,温度变化呈现先快后慢的趋势,在60 min内的温度变化趋势与标准升温曲线接近,在钢管填充的混凝土内,温度随着离中心距离的远近变化不同,内外侧最大温差达到400℃。此模拟分析为防屈曲支撑的灾后加固与修复提供了参考。

The paper adopts the method of numerical simulation analysis,according to the finite element analysis software Abaqus to establish an anti-buckling support model and then use temperature field analysis,using the ISO-834 international standard fire heating curve loading environment temperature,give the thermal parameters of each part of the model material,define the constraints,boundary conditions and interaction between components,through the heat transfer pathway of heat conduction,thermal convection,heat radiation,respectively,consider the one-two-three-four sides of the fire,after finite element analysis and calculation,The anti-buckling support as a whole and the temperature field distribution law of each component are obtained.After 60 min of fire,with the increase of the fire surface,the temperature of the cross-middle working section also gradually increases,but the maximum temperature is only 70℃,the temperature change on the outer buckling constraint unit and the connection section of the core unit shows a trend of first fast and then slow,the temperature change trend within 60min is close to the standard heating curve,in the concrete filled with steel pipes,the temperature varies with the distance from the center,and the maximum temperature difference between the inside and outside reaches 400°C.This simulation provides a reference for post-disaster reinforcement and repair of anti-buckling supports.