波纹钢腹板与平钢腹板组合T梁桥力学性能对比分析

Comparative Analysis of Load Bearing Performance of Concrete T-Beam Bridges with Corrugated Steel Webs and with Flat Steel Webs

为研究波纹钢腹板-混凝土组合T梁桥与平钢腹板-混凝土组合T梁桥力学性能优劣,以某3跨钢-混组合连续T梁桥为背景,采用非线性有限元软件建立2种腹板(平钢腹板和波纹钢腹板)形式的全桥实体模型,分析二者在车辆偏载作用下桥梁的纵向弯曲、横向挠曲、刚性扭转及稳定性能,并进行对比。结果表明:与平钢腹板-混凝土组合T梁桥相比,波纹钢腹板-混凝土组合T梁桥抗弯刚度可提高10%,桥面板抗裂性可提高约20%,两者剪力滞系数接近;两者纯扭刚度相差不大,整体横向挠曲性能接近;波纹钢腹板-混凝土组合T梁桥扭转刚度略大,跨中最大转角约为平钢腹板-混凝土组合T梁桥的85%,腹板扭转附加剪应力不到平钢腹板-混凝土组合T梁桥的一半;波纹钢腹板-混凝土组合T梁桥的前5阶屈曲因子是平钢腹板-混凝土组合T梁桥的5~8倍,线弹性稳定性极大,且腹板无需额外设置加劲肋,经济优势较大。

To examine the load bearing performance of the concrete T-beam bridge with corrugated steel webs and that with flat steel webs,a three-span continuous concrete T-beam bridge with corrugated steel webs was taken as the study background.The non-linear finite element software was used to establish the full-scale solid models of the continuous T-beam bridges with corrugated steel webs and with flat steel webs,respectively,to analyze and compare the longitudinal bending,transverse deflection,rigid torsion and stability of the two kinds of bridges under the action of vehicle eccentric loads.The results show that compared with the concrete T-beam bridge with flat steel webs,the bending rigidity of the concrete T-beam bridge with corrugated steel webs is 10% higher,the anti-cracking ability of the bridge deck is about 20% higher,and the shear lag coefficients of the two kinds of bridges are close.No big difference is found between the net rigid torsion of the two kinds of bridges and the integral transverse deflection of the two kinds of bridges is close.However,the torsional rigidity of the concrete T-beam with corrugated steel webs is a little bigger,the maximum rotation angle in the midspan is about 85%of that of the concrete T-beam bridge with flat steel webs,and the additional shear stress induced by web torsion is less than half of that of the concrete T-beam bridge with flat steel webs.The first five orders of the flexural factors of the concrete T-beam bridge with corrugated steel webs are 5 to 8 times of those of the concrete T-beam bridge with flat steel webs.The linear elastic stability of the concrete T-beam bridge with corrugated steel webs is very big,no additional stiffening ribs are needed to the webs,hence the concrete T-beam bridge with corrugated webs owns distinctive economic advantage.