大跨度变截面波形钢腹板组合箱梁抗扭性能研究

以某波形钢腹板组合箱梁桥为工程背景,建立三维有限元模型,以结构形式、墩高、墩高差以及波形钢腹板的厚度布置方式为变量,研究了这些变量对波形钢腹板组合箱梁桥抗扭性能的影响。研究结果表明扭转正应力的最大值主要出现在跨中截面附近,在桥墩截面附近也有较大的扭转正应力;波形钢腹板连续刚构桥的桥墩不高时,抗扭性能接近于波形钢腹板连续梁桥;波形钢腹板连续刚构桥的抗扭性能与墩高、墩高差成反比;波形钢腹板变厚度布置相比于采用最大厚度等厚度布置可以有效保证桥梁抗扭性能的同时减小桥梁运营过程中的挠度,另外还可以节省钢材。

Research on Torsion Resistance of Long Span Composite Box Girder with Variable Cross Section and Corrugated Steel Webs

With a composite box girder bridge with corrugated steel webs as the engineering background,a three-dimensional finite element model was established.Effects of these variables on the torsional behavior of composite box girder bridges with corrugated steel webs were studied by structural form,pier height,pier height difference and thickness arrangement of corrugated steel webs.The results show that the maximum value of torsional normal stress mainly appears near the mid-span section,and there is also a large torsional normal stress near the cross section of pier.When the pier of a continuous rigid frame bridge with corrugated steel webs is not high,the torsional behavior is close to a continuous beam bridge with corrugated steel webs.The torsional behavior of continuous rigid frame bridge with corrugated steel webs is inversely proportional to the pier height and pier height difference.The variable thickness arrangement of the corrugated steel webs can effectively ensure the torsional performance of bridge and reduce the deflection of bridge during its operation period compared with the equal thickness arrangement by the maximum thickness.In addition,steel can be saved.