城市轨道交通薄壁槽形梁车桥动力特性试验研究  

Experimental Study on Vehicle-Bridge Dynamic Characteristics of Thin-Walled Trough Girder Bridge for Urban Rail Transit

作　　者：吴亮秦[1] 吴定俊[1] 李奇[1] 

机构地区：[1]同济大学桥梁工程系,上海200092

出　　处：《中国铁道科学》2011年第4期31-37,共7页China Railway Science

基　　金：国家自然科学基金资助项目(50908178);高等学校博士学科点专项科研基金资助项目(20090072110044)

摘　　要：对城轨高架标准跨薄壁槽形梁桥进行现场测试,获得桥梁的频率、振型、阻尼比等自振特性,以及列车通过时桥梁的位移、振幅、应力、加速度响应和车体加速度的测试资料,对其进行的分析结果表明:梁体挠跨比小于规范限值,列车通过时没有发生共振现象,梁体竖向刚度满足要求;梁跨横向基频大于规范值,桥梁横向基频较小,墩顶横向振幅较大,梁体横向刚度满足要求,而桥墩刚度相对不足;道床板和腹板发生局部振动,当设计车速提高时,应注意行车线路和腹板的局部稳定性;梁体总体纵向弯曲动力系数小于规范值,而道床板局部横向弯曲动力系数远大于梁体总体纵向弯曲动力系数;桥面加速度在限值范围内,采用Sperling指标和ISO2631指标评判桥上列车乘坐舒适度均为优秀;薄壁槽形梁适用于轨道交通高架线。Field tests were conducted on a standard span thin-walled trough girder bridge for the elevated urban rail transit.The free vibration characteristics of the bridge,such as the frequency,mode and damping ratio were got.The test data for both the bridge and train during the train passing through the bridge, including the displacement,amplitude,stress and the acceleration responses of the bridge and the acceleration of the carbody were obtained and analyzed.The analysis results show that the deflection-span ratio of the girder body is less than the code limit.No resonance phenomenon occurs as the train passing through the bridge.The vertical stiffness of the girder body meets the requirements.The transverse fundamental frequency of the girder span is greater than the code value while the transverse fundamental frequency of the bridge is smaller.The lateral amplitude at the pier top is larger.The transverse stiffness of the girder body meets the requirements,whereas the stiffness of the pier is somewhat insufficient.Local vibration is found in the roadbed slab and the web.Therefore, more attention should be paid to the local stability of running lines and the web when the design speed is increased.The total longitudinal bending dynamic coefficient of the girder body is smaller than specification regulated value.However,the local transverse bending dynamic coefficient of the roadbed slab is much larger than the total longitudinal bending dynamic coefficient of the girder body.The acceleration of the bridge deck is within the limit.Judging by Sperling index and ISO2631 evaluation index,the ride comfort of the test train running on the bridge is found to be excellent.According to the test and analysis,thin-walled trough girder is proved to be suitable for elevated urban rail transit.

关 键 词：轨道交通 薄壁槽形梁 动力试验 车桥耦合 局部振动 乘坐舒适度 

分 类 号：U448.21[建筑科学—桥梁与隧道工程]