摘要
室外钢结构受火情况特殊,采用标准火灾升温曲线加载过于保守,因此宜结合实际火灾场景考虑。本文结合火灾模拟软件FDS与有限元软件ABAQUS,分析了某高炉室内火灾场景下的空气温度场分布,获得了室外钢柱表面热烟气温度,并通过公式计算出考虑火焰辐射作用的钢柱升温;将得到的钢柱温度导入有限元力学模型进行热力耦合分析,研究了高温作用下钢柱的变形以及截面应力分布情况,分析了受火过程中钢柱轴向位移的变化特点,比较了荷载比对受火钢柱位移的影响,结果表明:钢柱高温下轴向变形可分为三个阶段,即膨胀、压缩和破坏阶段;钢柱受火后支座处截面应力最大,且各柱支座截面应力分布类似;荷载比越大,钢柱受火后轴向压缩变形越大。
It’s too conservative to use the standard fire temperature-time curve loading on the outdoor steel structure which has a special fire condition. Therefore it is better to consider its fire resistance performance in combination with the actual fire situation. Combined with fire simulation software FDS and finite element software ABAQUS,the air temperature field distribution under the indoor fire situation of a blast furnace is analyzed,the temperature of heat flue gas on the surface of outdoor steel column is obtained,and the temperature rise of steel column considering the radiation effect of flame is calculated through the formula. The obtained steel column temperature is imported into the finite element model for thermo-mechanical coupling analysis,the deformation conditions,the axial displacement characteristic and the stress distribution of steel columns under high temperature are studied. In addition,the influence of load ratio on the displacement of steel columns under fire is compared.The results show that: the axial deformation of steel column with high temperature can be divided into three stages,namely,stage expansion,stage compression and stage failure;for the steel column exposed to fire,the stress at the bearing section is the largest,and the stress distribution at the section of each column is similar;the larger the load ratio is,the greater the axial compression deformation of the steel column will be.
作者
王建军
詹子娜
李磊
Wang Jianjun(China Academy of Building Research,Beijing 100013,China)
出处
《建筑科学》
CSCD
北大核心
2020年第1期117-122,共6页
Building Science
