Analysis of the causes of severe side wear of the high rail on metro curves by numerical simulation and field investigation

Two of the Shanghai metro lines suffered from severe side wear on the high rail, not only in sharp curves but also in large curves, and the service life of some rails on sharp curves was reduced by approximately 50% compared with the last rail replacement. Features and evolution rules for the rail side wear and the wheel flange wear were determined by field measurements and long-term monitoring. A rail wear prediction model, verified in our previous work, is used to reveal the influence of factors on rail wear. The results indicate that the poor lubrication condition at the rail gauge face is the main cause of severe side wear of the high rail, and the use of wheel profiles with low conicity and the loss of profile curvature of low rail profiles caused by the untimely maintenance also increase the side wear of the high rail. The service life of the high rail could be greatly extended by some countermeasures, such as repairing the worn shape of the low rail and repairing/improving the wayside lubrication system.