负弯矩区钢梁局部增强的连续组合梁抗火性能参数分析  

Locally Reinforced Continuous Composite Beam in Negative Moment Region Analysis of Fire Resistance Parameters

作　　者：周焕廷[1] 梁中政 ZHOU Huanting;LIANG Zhongzheng(School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学土木工程与建筑学院,武汉430070

出　　处：《武汉理工大学学报（交通科学与工程版）》2023年第3期492-498,504,共8页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：国家自然科学基金(51878528)。

摘　　要：文中利用ABAQUS建立了高温下纵向加劲肋增强受压翼缘的连续组合梁热-力耦合模型,研究纵向加劲肋增强负弯矩区受压翼缘的连续组合梁在火灾作用下的抗火性能.结果表明:在高温作用下,局部增强组合梁负弯矩区未发生钢梁腹板和下翼缘的局部屈曲,抗火能力得到显著增强.局部增强组合梁荷载比越大,临界温度越低;跨高比越小,横截面的温度梯度就越大,腹板及下翼缘更容易屈曲,且沿着纵向的屈曲的范围越大;纵向加劲肋长度约为腹板高度的2倍,厚度约为腹板厚度,组合梁的延性和抗火性能最好.A thermo-mechanical coupling model of continuous composite beams with longitudinal stiffeners and compressed flanges at high temperature was established by ABAQUS,and the fire resistance of continuous composite beams with longitudinal stiffeners and compressed flanges in negative moment zone was studied.The results show that under the action of high temperature,the local buckling of steel beam web and lower flange does not occur in the negative bending moment zone of locally reinforced composite beams,and the fire resistance is significantly enhanced.The greater the load ratio of locally reinforced composite beams,the lower the critical temperature.The smaller the span-height ratio is,the greater the temperature gradient of the cross section is,and the web and the lower flange are easier to buckle,and the greater the range of buckling along the longitudinal direction.The length of longitudinal stiffening rib is about twice the height of web,and the thickness is about the thickness of web.The ductility and fire resistance of composite beams are the best.

关 键 词：钢-混组合梁 负弯矩增强 纵向加劲肋 参数分析 抗火性能 

分 类 号：U441[建筑科学—桥梁与隧道工程]