斜拉桥与T型刚构的协作体系的振动特征研究

Theoretical Study on Dynamic Characteristics Analysis of Combined System of T-shape Steel Structure and Cable Stayed Bridge

广东金马大桥主桥为双索面混凝土独塔斜拉桥与T型刚构的协作体系,其独特结构体系的成功实施引起了工程界的巨大关注。基于大位移非线性弹性理论的广义变分原理,考虑了加劲梁轴向压缩应变能和剪切应变能的影响,建立了斜拉桥与T构协作体系空间耦合自由振动的大位移不完全广义势能泛函,通过约束变分导出了协作体系斜拉桥的加劲主梁的纵向振动、竖向挠曲振动、横向挠曲振动、扭转振动及加劲主塔的纵向振动及扭转振动的基础微分方程,并以数值计算验证推导的有效性,为协作体系桥的固有振动性状分析提供可靠的理论依据。

The main strucut of Guangdong Jinma bridge is a kind of special combined system of T-shape steel structure and single-tower cable stayed bridge. The successful implementation of this special structure has drawn more attention. In this paper, based on the generalized potential variational principal of nonlinear elasticity theory with large deflection,the incomplete generalized potential energy functional with large defletion is established on the space coupling free vibration of combined structure by considering the effect of axial compressive and shearing strain energy of stiffening girder. By constraint variation, the differential equations of longitudinal vibration,vertical vibration,lateral vibaration, and torsinal vibration of the main girde and the longitudinal vibration,lateral vibaration of the main tower have been derived .Though the comparison of the finite element computation among the dynanic charactistic of the Jinma bridge,shearing force system and the ordinary diagonal cable bridge system.Thus,it has comfirmed the superiority of the Jinma bridge rigidity collaboration system.