The Dynamic Characteristics Of Different Types Without A Frantic Jumble Of Track Structure Comparative Study

Ballastless tracks are the direction for the high-speed railway track structure development, and our country is strongly constructing high-speed railway mainly with ballastless tracks. However, our high-speed railway still lacks of mature experience in ballastless tracks. Therefore, intensive study on ballastless tracks is undoubtedly has important theoretical value and project application significance. This thesis conducted comparing research on the dynamic property of three main types of ballastless tracks (Rheda2000, Borg slab and Unit slab ballastless tracks), and from the perspective of noise and vibration reduction, conducted comparing research on the dynamic property with ladder-type sleeper track. The main completed work of this thesis is as follows:1.Based on the finite element method and Ansys software, respectively established dynamic analysis models of all the components of different types of ballastless tracks (Rheda2000, Borg slab and Unit slab ballastless tracks), on this basis, further established dynamic analysis models of the overall structure of the abovementioned ballastless tracks. Meanwhile, demonstrated that simulate the train load through a driving force function is reasonable through comparative analysis.2. Respectively calculated the natural vibration properties of Rheda2000, Borg slab and Unit slab ballastless tracks and ladder-type sleeper track. The comparative analysis results show that:the vertical natural frequencies of Rheda2000, Borg slab and Unit slab ballastless tracks are all higher than that of the ordinary ballasted track structure; the vertical natural frequency of Rheda2000is relatively the lowest while that of Borg slab is relatively the highest among the three types of ballastless tracks. However, the vertical natural frequency and stiffness of the ladder-type sleeper track are both the minimum comparing with the abovementioned three types of ballastless tracks.3. Respectively calculated the dynamic responses of the four types of ballastless tracks under the moving load of vehicles. Through a comparative analysis, found that:As the speed increases, the dynamic response of ballastless tracks increases; in the same speed, generally speaking, the dynamic response of ladder-type sleeper track is the highest while the Borg slab ballastless track has the lowest dynamic response; for the dynamic response of rail and slab (Road bed), the Unit slab ballastless track is higher than the Rheda2000ones; for the dynamic response of foundation (support layer) and roadbed, the Rheda2000ballastless track is higher than the Unit slab ones; comparatively, the dynamic performance of the Unit slab ballastless track is poor.4. Respectively calculated the influences of the main parameters such as rail fastener stiffness, mortar elastic modulus and roadbed stiffness on the natural vibration and dynamic responses of the Borg slab ballastless tracks and come to some regular rules.