火灾下考虑震损的方垫板加强T型节点抗火性能

利用已有试验验证方垫板加强T型节点数值分析模型,引入损伤变量,考虑参数直径比、径厚比、壁厚比、垫板长度与支管直径比及垫板厚度与主管厚度比,对震后火灾作用下方垫板加强T型节点抗火性能进行分析研究.结果表明:损伤变量对方垫板加强T型节点的临界温度影响较大,临界温度随着损伤变量的增大呈线性减小趋势;直径比、径厚比、壁厚比及垫板厚度与主管厚度比对方垫板加强T型节点的临界温度影响较小;垫板长度与支管直径比对方垫板加强T型节点的临界温度影响较大,且随着该比值的增大方垫板加强T型节点的临界温度减小;径厚比和壁厚比的增大会使方垫板加强T型节点临界温度发生小幅度的上升.

Fire resistance behavior of earthquake-damaged tubular T-joint reinforced with square doubler plate under fire

Based on the numerical analysis model of tubular T-joint reinforced with square doubler plate verified by existing experimental tests, by introducing damage variable and considering the parameters, such asdiameter ratio, diameter-to- thickness ratio,wall thickness ratio, doubler plate length-to-brace diameter and doubler plate thickness-to-chord thickness, fire resistance of tubular T-joint reinforced with square doubler plate was analyzed under post-earthquake fire. The results show that the critical temperature of tubular T-joint reinforced with square doubler plate is affected by the damage variable, and the critical temperature decreases linearly with the increase of the damage variable; diameter ratio, diameter-to- thickness ratio, wall thickness ratio and doubler plate thickness-to-chord have little influence on the critical temperature of the tubular T-joint reinforced with square doubler plate; doubler plate length-to-brace diameter has a great influence on the critical temperature of the tubular T-joint reinforced with square doubler plate, and the critical temperature of the tubular T-joint reinforced with square doubler plate decreases with the increase of this ratio.