新型装配式钢混组合梁柱节点受火温度场研究

Research on temperature field of a new assembled steel-concrete composite beam-column joint under fire

对一种新型装配式钢混组合梁柱节点开展了足尺火灾试验,对比分析了节点梁和节点柱不同截面不同测点的温度场。同时基于有限元软件ABAQUS进行了梁柱节点受火下温度场的模拟分析,分析结果与试验结果吻合良好,验证了模型的可靠性。研究结果表明,1)新型装配式钢混组合梁柱节点在火灾下的温度场分布呈外高内低的趋势,在受火1h后,试件梁柱截面表层50mm以内的混凝土最高温度基本在400℃左右,而截面中心处温度均在200℃以下,预测梁柱节点的承载能力下降有限;2)梁端钢接头的存在会使梁温度场发生重分布;3)火灾下梁柱节点核心区温度较低,是相对安全的。

The fire experimental study was carried out on a full-scale new assembeled steel-concrete composite beam-column joint.The temperature field under fire of different sections and different measuring points of joint beam and joint column were compared and analyzed.Finite element analysis was also conducted based on the software ABAQUS to simulate the temperature field of beam-column joint under fire.The analysis results were in good agreement with the test results,which verifies the reliability of the model.The results show that:1)the temperature field distribution of the new assembled steel-concrete composite beam-column joint under fire was gradually decreasing from the outside to the inside.After one hour of fire,the maximum temperature of the concrete within 50mm of the surface layer of the beam column section reached about 400℃,while the temperature of the concrete at the core of the section was below 200℃,which indicates that the decrease in bearing capacity of the joint was limited;2)the existence of steel joint at the end of beam would make the temperature field redistribute;3)the temperature in the core area of beam-column joint under fire was low and relatively safe.