Research On Vibration-reduction Performance Of CrtsⅢ Slab Ballastless Track

With the rapid development of high-speed railway in China, the issue of track vibration has becoming more and more serious. Due to the application of ballastless track for the high-speed railway in China, it’s very meaningful to research on the vibration-reduction properties of ballastless track. The CRTSIII slab track with self-owned intellectual property in China is considered as the research object in this paper. The theory of vehicle-track coupling dynamics is used to establish the vehicle-track-sub-foundation vertical coupling model with the method of ANSYS/LS-DYNA and a systematic study on vibration-reduction properties of CRTSIII slab track has been conducted.Firstly, according to the structural characteristics of the vehicle and track system, the system has been simplified reasonably to establish the vehicle-CRTS III slab track-sub-foundation dynamic vertical calculation model. The calculation parameters are determined based on the physical truth.Secondly, by means of dynamic analytical software ANSYS/LS-DYNA, the model has been solved. The influence of changing fastener rigidity and anti-vibration pad rigidity on the dynamic performance of track structure has been analyzed. With the method of AHP (analytic hierarchy process), in favor of the overall performance of the track structure, the reasonable fastener rigidity that is from30-50kN/mm is determined as well as the area rigidity of anti-vibration pad varying from80～100MPa/m.Finally, the theoretical calculation results have been compared with the test results on the Chengdu-Dujiangyan line. The results show that there is some difference between the theoretical results and in-situ test results. However the law achieved by two methods basically keeps the same, which proves the rationality of the calculation results. The calculation and test results indicate that the mechanism of vibration-reduction slab track lies in vibration isolation. Demarcated by the anti-vibration pad, the vibration of the upper structure (rail and track slab) of the vibration-reduction slab track is a little larger than that of common slab track, but the vibration of the sub-structure (baseplate and bridge) of the vibration-reduction slab track decreases significantly with the obvious vibration-reduction effect.