RAILROAD CURVE TRANSITION SPIRAL DESIGN METHOD BASED ON CONTROL OF VEHICLE BANKING MOTION

摘要

Transition spirals for successive sections of railroad track with different degrees of curvature are designed by first specifying the manner in which the bank angle of the track should change with distance along a transition spiral. Functional forms for bank angle are provided as a function of distance along the spiral (Figs. 1-8), which can also be used in traditional conceptual frameworks, and interpreted in that context to define track curvature as a function of distance. Also included are functional forms obtained by raising the longitudinal axis about which bank angle change takes place so that the axis is above the plane of the track. The resulting transition spirals (Figs. 9 and 10) reduce the transient lateral accelerations to which passengers are subjected when passenger vehicles traverse the spirals and reduce the damaging transient lateral forces that heavy freight locomotives and freight cars apply to the track structure near the ends of the spirals.