中小跨径双主梁形式钢板组合梁截面优化设计

Section Optimization Design of Double-beam Steel Plate Composite Bridge with Medium and Small Span

为提出结构安全,经济适宜的中小跨径钢板组合梁桥,提升公路桥梁的建设品质,以辽宁省内两座跨径分别为5×30 m和5×35 m的双主梁钢板组合连续梁桥为依托工程,采用有限元建模对这两种跨径的双主梁组合梁桥进行参数分析,以主梁跨中挠度及单位面积用钢量为评价指标,提出以上两种跨径组合梁桥的推荐梁高及合理板件配置。结果表明:在关键截面应力保持相同水平的条件下,跨中挠度及用钢量均随主梁高度的增加而减小,综合考虑视觉效果,经济性和城市空间限制等因素,最终分别选择1.9 m和2.1 m作为5×30 m和5×35 m两种跨径的双主梁钢板组合梁桥的推荐梁高。

In order to propose a structurally safe and economically suitable small and medium-span steel plate composite beam bridge to enhance the quality of highway bridge construction,two double-span steel plate composite continuous beams with a span of 5×30 m and 5×35 m in Liaoning Province were adopted.The bridge was based on the supporting project.The finite element modeling was used to analyze the parameters of these two spans of the double-girder composite girder bridge.With the deflection of the main girder span and the amount of steel used per unit area as evaluation indicators,the above two types of span combinations with recommended beam height of beam bridge and reasonable plate configuration are proposed.The results show that under the condition that the critical section stress remains at the same level,the deflection and steel consumption of the mid-span decrease with the increase of the height of the main beam.Taking into account factors such as visual effects,economy and urban space constraints,the final choices are 1.9 m and 2.1 m are the recommended beam heights for double-girder steel plate composite beam bridges with two spans of 5×30 m and 5×35 m.