Abstract:

With the development of railway technology in the direction of high-speed and heavy-load, the research on the railway has become more and more significant. The relationship between the sleeper settlement under stable action and the ballast particle movement under the sleeper is analyzed in the proposed study. The method of coupling finite element and discrete element is utilized to study the sleeper settlement and track bed settlement. A 500 mm×230 mm×160 mm simplified sleeper cuboid model with a reduction ratio of 8∶1 is established by using finite element software, and the element nodes of the sleeper are extracted. The discrete element replacement of node coordinates is implemented through the discrete element software EDEM API to construct the sleeper discrete element model, and uses spherical particles to splice ballast particles of different shapes to complete the sleeper-track bed discrete element model. The discrete-element software is adopted to build the sleeper-track bed shrinkage model. At the same time, a test model of the same size as the sleeper model is established, and the validity and reliability of the sleeper-track bed model was determined through comparison and verification. The sleeper and track bed settlements under different excitation frequencies are analyzed, and the sleeper settlement law is obtained. It is determined that the sleeper settlement reaches the maximum when the excitation frequency reaches 36 Hz during the stabilization process. The relationship between the sleeper settlement and the stabilization operation time is obtained. As the stabilization process proceeds, the track bed settlement increases, and the settlement effect in the area directly below the sleeper is better.

Key words: ballast bed, finite element, discrete element, coupling, dynamic characteristics, sleeper settlement