钢框架边跨梁抗火性能试验研究和理论分析

对3层钢框架结构边跨梁在火灾作用下的性能进行足尺试验研究，试验中测量了炉温、钢梁和混凝土板沿截面高度的温度场分布以及钢梁和混凝土板的竖向位移。结果表明：钢梁下翼缘、腹板和烟气的温度基本一致；混凝土板内的温度滞后于钢梁温度，且在钢梁降温阶段，混凝土板温度持续升高，因此混凝土板限制了钢梁升温阶段的膨胀和降温阶段的收缩；钢梁在122 min的升温过程中变形较小，且在升温阶段变形就开始恢复，最终出现向上的竖向位移，这是框架结构中钢梁火灾行为区别于单个构件火灾行为的特点之一，表明框架结构中与混凝土楼板形成整体的边跨梁具有较强的抗火性能；最后钢梁上下翼缘焊缝被拉裂破坏，因此在工程应用中应尽量避免工地现场施焊的全焊接节点。利用非线性有限元软件对试验梁进行了火灾反应分析，得出了试验梁的温度场分布和位移反应的变化规律。有限元分析结果和试验结果基本一致，验证了有限元分析模型的正确性和可行性。

Experimental and analytical studies on performance of edge beams of steel framed building subjected to fire

This paper studies the performance in fire of the edge beam in a full-scale three-story steel framed building.The temperature distribution across the steel beam and reinforced concrete slab sections was measured.The displacements at different sections of steel beam and reinforced concrete slab were recorded during the experiment.It was found that the temperature at the bottom flange and web of steel beam was almost the same as that of the smoke in the furnace.But the temperature at the top flange of beam wa...