新型自锚式悬索-连续梁组合体系人行桥理论分析及设计

Theoretical analysis and design of new self-anchored suspension cable-continuous beam composite system pedestrian bridge

中文关键词: 人行桥  自锚式悬索-连续梁组合体系  静力分析  模态分析  结构优化

英文关键词: pedestrian bridge  self-anchored suspension cable-continuous beam composite system  static analysis  modal analysis  structure optimization

中文摘要:

      由于常规对称布局的索-梁组合体系难以适用于城市人行桥的设计，为跨越非对称复杂地形，提出了一种新型自锚式悬索-连续梁组合体系的概念．该组合体系是基于三维空间中的弹性变形与刚体扭转的组合机制，采用新式的连接件进行索、梁、塔的三位一体连接组合．全面分析了该组合体系的静力、动力及稳定性等力学行为，提出了改善结构力学性能的方法，并对该组合体系进行了减振设计；最后采用多目标遗传算法(MOGA)对新组合体系结构进行了优化．研究结果表明，该体系在有限地形中布局桥梁结构具有较大优势，MOGA优化设计方法可实现该体系桥梁结构的合理布局、安全受力．研究成果可为复杂地形边界条件下的人行桥设计及其结构优化提供参考借鉴．

英文摘要:

      Since the conventional cable beam composite system of symmetrical layout is not suitable for the design of urban pedestrian bridges, a concept of a new self-anchored suspension cable-continuous beam composite system is proposed to span asymmetric complex terrain. The composite system adopts a new type of connector to form three in one connection combination of cables, beams and towers, which is based on the combination mechanism of elastic deformation and rigid body torsion in three dimensional space. The static, dynamic and stability mechanical behaviors of the composite system are analyzed comprehensively, and the method to improve the mechanical properties of the structure is put forward, and the anti vibration design of the composite system is carried out. Finally, multi objective genetic algorithm (MOGA) is used to optimize structure for the new composite system. The results show that this system has great advantages in the layout of bridge structures in the limited terrain, and the MOGA optimization design method can realize the reasonable layout and safty of the bridge structure of the system. The research can provide reference for pedestrian bridge design and structure optimization under complex terrain boundary conditions.