BENEFITS OF DIPPED VERTICAL ALIGNMENTS FOR RAIL TRANSIT ROUTES

Dipped track profiles between mil transit stations can significantly r educe propulsive energy, braking energy, and travel times. This work q uantifies their potential benefits for circumstances reflected in vari ous values for dips, speed and acceleration limits, station spacings, and available power. A deterministic simulation model has been develop ed to precisely estimate train motions and performance using basic equ ations for kinematics, resistance, power, and braking. For a 1% dip (i .e. a vertical dip equal to 1% of station spacing) in which gradients never exceed 4%, our results show savings (compared with level tracks) exceeding 9% for propulsive energy, 15% for braking energy, and 5% fo r travel time between stations.