局部火灾条件下H型钢梁温度分布试验及模拟
Experiment and Simulation of Temperature Distribution for H-shape Beams under Local Fire Condition
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摘要: 在小空间室内对H型钢梁进行了局部火灾试验, 热源温度为880 ℃, 采集沿H型钢梁高度方向的温度分布, 并与压型钢板-混凝土组合梁在局部火灾下的试验数据进行比较; 在试验基础上采用有限元软件ANSYS数值模拟反推所需的各种热物理参数, 并模拟出工程中常用的几种窄翼缘H型钢在小空间室内火灾条件下的温度场。结果表明: 火灾持续30 min后H型钢达到很高的温度, 且钢梁各个部分的温度分布差异很大, 下翼缘的最高温度达到630 ℃, 而上翼缘只有300 ℃; H型钢梁的温度梯度从下向上逐渐增大, 温度随时间的变化呈非线性分布; 试验结果证明了模拟的准确性。Abstract: H-shape steel beams were examined under local fire condition in a small space where the heat source temperature was 880 ℃, the temperature distribution of the H-shape steel beams along the height direction was collected and compared with the experimental data from profiled steel sheet-beton built-up beams under local fire condition. Temperature fields of several thin wing H-shape steel beams normally used in engineering were simulated under local fire condition in a small space, using thermal physical parameters deduced from numerical simulation by finite element software ANSYS and based on the experimental data. Results show that H-shape steel got a high temperature in a fire for 30 min, and the temperature distribution show great difference in each part of the beam, the highest temperature of the bottom flange was 630 ℃ while it was only 300 ℃ of the top flange.The temperature gradient of H-shape steels increased gradually from the bottom to the top, the temperature-time curves were nonlinear. The experiment results proved the accuracy of the simulation.