高烈度区高速铁路多跨长联连续梁桥设计

Design of multi-span continuous girder bridge structure of high-speed railway in high intensity area

高烈度地震区高速铁路跨越黄河特大桥,为满足黄河主河道防洪及通航要求,并综合考虑河床演变复杂多变的特点,兼顾标准化设计的指导思想,采用(64+3×110+64)m的多跨预应力混凝土连续梁桥跨越黄河主河道。设计采取合理的预应力钢束布置,减小梁体上下缘应力差等措施有效控制主梁徐变变形;通过选择合理的主梁合拢方案,在实现最优梁体线形同时最大化缩短施工工期。大桥桥址处地震动峰值加速度为0.34g,采用双曲面摩擦摆减隔震支座和粘滞阻尼器相结合的减隔震措施,合理优化墩身基础结构尺寸,并有效降低桥梁震后破坏程度,实现桥梁安全性和经济性的协调统一。

In order to meet the flood control and navigation requirements of the main river channel of the Yellow River,and considering the complex and variable evolution of the river bed,multi-span prestressed concrete continuous beams(64+3 × 110+64)m are adopted to cross the main river channel of the high-speed railway in the high intensity earthquake area.The creep deformation of the main beam is effectively controlled by controlling the stress difference between the upper and lower edges of the beam and optimizing the layout of prestressed steel bundles.By choosing a reasonable closing scheme of the main beam,the optimal alignment of the beam body can be realized and the construction period can be shortened as much as possible.The peak acceleration of ground motion at the bridge site is 0.34g,and the damping measures combining hyperboloid frictional pendulum bearing and viscous damper are adopted to optimize the size of pier foundation structure reasonably and effectively reduce the post-earthquake damage degree of the bridge.The bridge design realizes the coordination and unity of bridge safety and economy.