快速架设的高强铝合金桁架桥梁承载能力研究

Research on bearing capacity of high strength aluminum alloy truss bridge with rapid erection

针对应急条件下桥梁快速架设的结构选型及承载力问题,提出了快速架设的高强铝合金桁架桥梁解决方案,研究了不同跨径、不同桁架单元组合模式下高强铝合金装配式桥梁的承载能力,研究表明:高强铝合金装配式桥梁的承载能力满足公路-I级载荷要求,相较于传统的装配式公路强桥,具有质量更轻、跨越能力更大的特点。研究基本结论如下:1)高强铝合金桁架桥梁满足强度和刚度的要求,结构主体应力能控制在370MPa以内,活载挠度可控制在跨径的1/200之内;2)单构件最大重量能控制在252kg以内;3)屈曲稳定分析表明,结构能满足整体和局部稳定;4)车桥耦合动力分析表明控制车辆的通行速度是有效降低车桥响应的手段,三种通行速度下车桥未发生共振现象。

In view of the structural selection and bearing capacity issues of rapid bridge erection under emergency conditions,a solution for rapid erection of high-strength aluminum alloy truss bridges was proposed.The bearing capacity of high-strength aluminum alloy fabricated bridges with different spans and different truss unit combinations was studied.The study showed that the bearing capacity of high-strength aluminum alloy fabricated bridges meets the requirements of highway Class I load,and has a lighter weight coMPared to traditional fabricated highway bridges Greater leapfrog capability.The basic conclusions of the study are as follows:1)The high-strength aluminum alloy truss bridge meets the requirements for strength and stiffness,the stress of the main structure can be controlled within 370MPa,and the live load deflection can be controlled within 1/200 of the span;2)The maximum weight of a single component can be controlled within 252kg;3)The buckling stability analysis shows that the structure can satisfy both global and local stability;4)The dynamic analysis of vehicle bridge coupling shows that controlling vehicle speed is an effective means to reduce vehicle bridge response,and no resonance phenomenon occurs on the vehicle bridge at the three speeds.