【摘要】 为评价预应力混凝土桁架连续刚构桥的动力性能,以湖北省归州大桥动力试验为背景,测试了结构的频率、振型、阻尼比和不同行车速度、不同路况下结构的冲击系数。建立了基于不同假定的3种空间有限元计算模型,计算了结构的振动频率和振型,与实桥动力试验结果进行了对比分析;研究了结构刚度、横向联系、桥墩高度、边界约束条件等参数对结构动力特性的影响。结果表明,横铺桥面板对提高结构横向刚度和扭转刚度有较大的贡献;结构的横向刚度和纵向刚度相对竖向刚度和扭转刚度较小;结构振动衰减正常,桥面平整度较好,具有良好的行车性能;结构整体刚度、桥墩高度及边界约束条件是影响结构横向和纵向振动的主要因素;横向联系是影响结构的局部扭转振动的主要因素。更多还原

【Abstract】 For evaluation of the dynamic property of the prestressed concrete continuous rigid-frame bridge,dynamic loading tests were made on Guizhou Bridge in Hubei Province,the vibration frequencies,modes,damping ratios and impact coefficients with different driving speeds and surface roughnesses of bridge deck were tested.Three space finite element calculation models based on different kinds assumptions were built.The vibration frequencies and modes of the bridge were calculated,and the comparative analysis between the calculation result and the test result was carried out.Effects of structural parameters,such as structural rigidity,transverse connection,pier height and boundary condition,on structural dynamic property was studied.The result indicates that(1) cross-deck slab’s rigidity can not be ignored owing to its more contribution to increase structural transverse and torsion rigidities;(2) structural transverse and longitudinal rigidities are relatively small than vertical and torsional rigidities;(3) structural vibration attenuation is normal,surface of bridge deck has a good flatness condition,and driving is comfortable;(4)structural rigidity,pier height and boundary condition are major factors to affect structure transverse and longitudinal vibration property,while traverse connection way has great effect on structural partial torsion vibration.更多还原