高速铁路桩板结构路桥过渡段无砟轨道动力特性试验研究

桩板结构被广泛应用于我国高速铁路深厚软土地区地基处理,其对路基与桥梁间不均匀沉降控制具有显著效果,但针对桩板结构路桥过渡段上无砟轨道的结构动力特性却鲜有研究。以杭长高铁桩板结构路桥过渡段为研究对象,采用现场实车测试,分析不同行车速度下过渡段和相邻桥梁上无砟轨道结构动力特性及其差异。研究结果表明,随行车速度增加,钢轨和轨道板加速度呈指数增长,轨道板动位移呈线性增长;同一行车速度下,过渡段和桥梁上轨道结构振动无突变现象,差异性小;由行车测试数据拟合结果预测行车速度达到350 km/h时,过渡段上钢轨加速度约为2 324 m/s~2,轨道板动位移约为0.49 mm,轨道板加速度约为17.89 m/s~2。

Experimental Study on Dynamic Characteristics of Ballastless Track in Pile-plank Structure Subgrade-bridge Transition Section

Pile-plank structure is widely used in the treatment of the foundation in deep soft soil area and it has significant effect on the control of uneven settlement between subgrade and bridge. However, there is very few research on the dynamic characteristics of the ballastless track in the subgrade-bridge transition section of pile-plank structure. In order to study the dynamic characteristics and differences of the ballastless track structures in transition sections and adjacent bridges under different train speeds, the Hangzhou-Changsha High-speed Railway is researched with field test. The results show that, with the increase of the train speed, the acceleration of the rail and track slab increase exponentially, and the dynamic displacement of the track slab increases linearly. Under the same train speed, the vibrations of the track structures in the transition section and on the bridge have no sudden changes, and the differentiation is small. The test data fitting predicts that when the train speed reaches 350 km/h, the vibration acceleration of the rail is about 2 324 m/s~2, the dynamic displacement of the track slab is about 0.49 mm, and the vibration acceleration of the track slab is about 17.89 m/s~2