Determination of wheel loading reduction in railway track with unsupported sleepers and rail irregularities

Abstract

This study investigates the simultaneous effects of unsupported sleepers and rail random irregularities on track displacement and wheel load reduction, by means of numerical simulations with vehicle-track coupling. Vehicles are simulated as multibody systems comprising the major vehicle masses and suspension systems with nonlinear stiffness and damping. Flexible track with rail, sleeper and ballast components is considered using finite element and multibody programs. Numerical results of the simulations are in good agreement with field test measurements. Findings show that in tracks with less than four unsupported sleepers the vehicle is able to move at a speed of 110 km/h; with a higher number of unsupported sleepers the vehicle is vulnerable to derailment. The vehicle speed has no effect on the maximum rail displacement in tracks with less than four unsupported sleepers.