基于欧洲规范的组合梁叠合桥面板横向受力分析

Transverse Mechanical Property of Composite Deck System Consisting of Steel Trusses and Precast Concrete Slabs Together with a Cast-in-Situ Layer

为研究钢筋桁架叠合桥面板的横向受力性能,以格鲁吉亚E60高速公路上某主跨60 m组合梁桥为背景,针对14.4~16.6 m桥宽(5 m宽梁间距和2.2~3.3 m悬臂长度)采用“70 mm厚钢筋桁架预制板+180 mm厚现浇层”叠合桥面板方案,基于欧洲规范,应用弹性分析方法和MIDAS Civil有限元分析软件分别对施工阶段以及使用阶段不同桥宽桥面板横向受力进行分析。结果表明:除16.6 m宽桥面板外支点截面需要在原设计基础上加强配筋外,14.4 m和15.2 m宽桥面板的受力均满足欧洲规范要求;“70 mm厚钢筋桁架预制板+180 mm厚现浇层”叠合桥面板方案适用于5 m宽梁间距和2.2~3.3 m悬臂长度的桥面板,可满足实际桥梁结构受力需求。

The transverse mechanical property of bridge deck system consisting of trusses made of reinforced bars,precast concrete slabs and a cast-in-situ layer is studied.A composite girder bridge with main spans of 60 m of E60 Highway in Georgia is used as a case.To accommodate a deck width of 14.4 to 16.6 m(the steel I girders are transversely spaced at 5 m and the cantilevers flanked the steel I girders are 2.2 to 3.3 m long),a solution of 70 mm-deep steel trusses and precast concrete slabs together with 180 mm-thick cast-in-situ layer is proposed.Based on Eurocode,an elastic analysis supplemented with finite element analysis in MIDAS Civil was conducted to analyze the transverse mechanical property of the deck system of different widths at the construction and service stages,respectively.As per the analysis,extra reinforcement is needed for the two outermost cross-sections in the 16.6 m-wide deck,and the load bearing capacities of the 14.4 m-and 15.2 m-wide decks meet the code requirements.The proposed deck system solution is applicable to the bridge where the steel girders are transversely spaced at 5 m and the cantilevers flanked the steel I girders are 2.2 to 3.3 m long and enables the bridge to achieve the expected load bearing requirements.