季节冻土区夏季轨道结构振动反应现场监测

为了研究季节冻土区在无冻土层时列车正常行驶引起的铁路轨道结构振动反应特征与衰减规律,针对哈尔滨-大庆铁路夏季振动反应进行了现场监测.合理定义振动反应加速度特征值,并结合加速度反应时程曲线对钢轨、轨枕、路基和场地振动反应特性取得定量认识,提出用负幂次函数等拟合路基振动反应衰减关系并给出拟合参数;获得列车行驶速度、车辆结构、重载等对钢轨、轨枕、路基的振动反应影响显著,无缝线路列车高速行驶过程中钢轨纵向振动不可忽视且值得深入研究等结论.

Field monitoring on railway structure vibration response at seasonal frozen region of Daqing in summer

Based on the field monitoring of vibration response of Harbin-Daqing railway in summer, characters and attenuation laws of railway structure induced by running train are researched in seasonal frozen soil region with no frozen layer. Acceleration eigenvalue of vibration response is defined, and history curve of acceleration response is considered, some new results have been drawn about the vibration response of rail, sleeper, subgrade and ground, moreover, using the negative power function to fit the subgrade vibration, and the fit parameters are given. Furthermore, the effects of the running speed, the vehicle structure, over loading of the train on the vibration responses of the rail, sleeper and subgrade are notable, and the vertical vibration of the seamless rail induced by steering-train with high speed should not be ignored and needs to be further investigated. The above results take on important role in the following aspects: (1) being used to compare with the vibration response of the railway in the region with frozen soil, (2) providing the fundamental datum of Field monitoring to further investigate the rail transit and to improve the criterion of the rail construction in the cold region.