Verification of a Transit Vehicle’s Curving Behavior and Projected Wheel/Rail Wear Performance

A test program was undertaken at the Transportation Test Center in Pueblo, Colorado, to investigate whether modifications to the truck design, particularly a reduction of the primary yaw stiffness, would reduce wheel and rail wear on a new rapid transit system. The test program examined the behavior of the trucks during the negotiation of a number of curves typical of those encountered in revenue service. Test results compared favorably with predictions from a mathematical model of the truck’s curving behavior and, subsequently, the model was used to evaluate a number of truck parameter variations. Results show that the reduction in primary yaw stiffness produced a large improvement in curving performance. This paper also quantifies the effects of axle misalignment and discusses the need for experimental data to relate a wear index to wheel and rail wear.