Discrete element analysis of breakage of irregularly shaped railway ballast

Abstract

In order to reduce the maintenance costs of ballasted railway track and improve passenger comfort, the railway ballast particle breakage and its effect on track settlement need to be better understood. The failure process of individual railway ballast loaded between flat platens is simulated using the discrete element method, considering its irregular shape with the incorporation of parallel bonds. The tensile strength, the stress of a survival probability of 37% of samples, is obtained and compared with laboratory results from published literature for the verification of DEM simulations. The evolution to failure of the particle is understood from the stress-strain curve and progressive failure modes. The internal breakage mechanisms are analysed by tracking the accumulation of bond breakage number and the contact force distributions.

Keywords:

• discrete element method
• breakage
• irregular shape
• parallel bond
• railway ballast

Additional information

Funding

This work was supported by National Natural Science Foundation of China Key Project- Joint Fund of High Speed Railway Basic Research [Grant No. U1234209], and the National Program on Key Basic Research Project (973 Program) [2010CB731502].