钢-混组合桥面系截面设计参数研究

Research on Cross Section Design Parameters of the Steel-concrete Composite Bridge Deck

钢-混凝土组合桥面系在大跨度桥梁中的应用日趋广泛,其结构及形式多借鉴于建筑结构。以某大跨悬索桥钢-混组合桥面系为例,结合ANSYS有限元程序的Workbench平台Design-Exploration模块进行实验设计,对组成钢混组合桥面系的混凝土板、钢纵梁及钢桁架等结构参数对组合截面力学性能的影响进行了相应研究。结果表明:混凝土板厚度的变化对钢-混组合桥面系力学性能影响较为明显,钢纵梁厚度和钢桁架高度变化产生的影响相对较小。混凝土板的高度和钢纵梁厚度变化时产生的效应基本相同,组合桥面系竖向挠度和钢纵梁应力极值随着混凝土板厚度或者钢纵梁厚度增加而增加;钢桁架高度在从低到高的变化过程中,组合桥面系竖向挠度逐渐减小,钢纵梁极值压应力和极值拉应力分别出现先增大后减小和先减小后增大的现象。

The steel-concrete composite bridge deck system is widely used in long-span bridges, and its structural form are mostly referenced to the building structure. Taking a steel-concrete composite bridge deck of a long-span suspension bridge as an example, combining with the Workbench Platform of ANSYS finite element program, a Design of Experiment is carried out with Design-Exploration module. The influence on the mechanical properties of the section parameters, such as concrete slabs, steel longi- tudinal girders and steel trusses are studied. Results show that the mechanical properties of steel-concrete composite deck are less affected by the thickness of steel longitudinal girders and the height of steel truss compared with the variation of thickness of concrete slab. The effects induced by the variation of the thickness of the concrete slab and the thickness of the steel longitudinal girders are basically the same. The vertical deflection of the composite deck and the stress extreme values of the steel longitudinal girder are increased with the thickness of the concrete slab or the thickness of the steel longitudinal girder. During the changing process of the height of steel truss from low to high, the vertical deflection of the composite deck is gradually reduced, and the extreme compressive stress of the steel longitudinal girder will change from increase to decrease, whereas the ultimate tensile stress is opposite.