Lateral resistance of polyurethane-reinforced ballast with the application of new bonding schemes: Laboratory tests and discrete element simulations
To mitigate the ballast flight risk in the high-speed railway, this paper presents three new polyurethane bonding schemes which have negligible influence to tamping operations. With the application of these bonding schemes, a series of laboratory tests indicated that the polyurethane-reinforced ballast exhibited much larger lateral resistance than the ordinary ballast by 31% at least. Discrete element simulation results further demonstrated that the polyurethane improved the load-bearing capacity of the ballast at the particle scale through effectively restraining the particle movement. Therefore, the proposed bonding schemes ensure adequate lateral ballast resistance and are effective measures for improving the ballast performance.
Keywords: High-speed railway, Ballast, Polyurethane, Discrete element method, Lateral resistance, Single sleeper pull-out test,