大跨度塔梁固结独塔斜拉桥抗震性能研究

Study on Seismic Performance of Long-Span Pylon-Girder Consolidated Single-Pylon Cable-Stayed Bridge

摘要:

为研究大跨度塔梁固结独塔斜拉桥的抗震性能，以主跨350 m独塔独柱斜拉桥——淮南淮河大桥为研究对象，针对其非对称结构特性展开系统性抗震研究。基于精细化有限元模型，通过动力特性分析，提取结构自振频率与模态，揭示独塔固结体系在动力响应中的薄弱环节；此外，相较于半漂浮体系，塔梁固结体系在地震作用下的特性表现为塔底弯矩减小59%，但梁端位移增大58%。通过阻尼器参数敏感性研究，优化黏滞阻尼器关键参数，可减小塔底弯矩11%、塔底剪力12%。

Abstract:

To study the seismic performance of a long-span pylon-girder consolidated single-pylon cable-stayed bridge, taking Huainan Huaihe River Bridge - a single-pylon single-column cable-stayed bridge with the main span 350 m as a research object, the systematic seismic study is conducted on its asymmetric structural characteristics. Based on a refined finite element model, the dynamic characteristic analysis is performed to extract the natural vibration frequencies and modes of the structure, and to reveal the weak links in the dynamic response of the single-pylon consolidation system. In addition, compared with the semi-floating system, the characteristics of the consolidated system under seismic action are manifested as a 59% reduction in the bending moment at the bottom of the pylon, but a 58% increase in the displacement at the end of girder. Through a sensitivity study of damper parameters, the key parameters of viscous dampers are optimized to reduce the bending moment at the bottom of the pylon by 11% and the shear force at the bottom by 12%.