沌口长江公路大桥索梁锚固区钢锚箱结构设计优化

Structural Design Optimization of Steel Anchor Boxes in Cable-Girder Anchorage Zone of Zhuankou Yangtze River Highway Bridge

以沌口长江公路大桥索梁锚固区的钢锚箱结构为依托,基于局部传力的不同力学形态分别建立了考虑线性、材料非线性以及接触非线性的有限元数值模型,对钢锚箱式连接构造的关键设计参数进行了影响性分析,从节省用钢量和减少应力集中的角度提出了优化设计方案,并对优化后锚箱结构在各种工况下的力学性能进行了计算和验证。分析过程中主要考虑了锚固板长度、板厚、锚垫板及承压板厚度和钢箱梁边纵腹板厚度对钢锚箱受力的影响,并利用回归公式揭示了部分设计参数对结构响应的影响规律,其设计方法和思路能够保证锚固结构的安全性和经济性,并为同类桥梁的设计提供参考。

Based on the steel anchor box structure of the cable-beam anchorage zone of the Zhuankou Yangtze River Highway Bridge,a finite element numerical model considering the linearity,material nonlinearity and contact nonlinearity is established based on the different mechanical forms of the local force transmission.The key design parameters of the connection structure are analyzed,and the optimal design scheme is put forward from the point of saving steel and reducing the stress concentration.The mechanical properties of the optimized anchor box structure under various working conditions are calculated and analyzed.The influence of the length of anchorage plate,the thickness of anchor plate,bearing plate and longitudinal webon the steel box girder are considered in the analysis,and the regression formula is used to reveal the influence of som e design parameters.The design method and idea can guarantee the safety and economy of the anchored structure and provide reference for the similar bridge design.