ON METHODS USED FOR SETTING THE CURVEFOR RAILWAY TRACKS

The regular efforts to enhance vehicle velocities and obtain even higher speeds on the railways need high quality track. The measure of track quality is the quality of the curves linking intersecting but multiple directional straight lines. Presently, transition curves are provided on track suitable for higher speeds to negotiate the contact stresses and dynamic effects generated due to lateral acceleration. Despite the less literature available on the area, methods exist for planning transition curves taking account of the dynamics of movement. Most of them are based on the effects or non-compensated lateral acceleration changes in such acceleration and the shock of sudden displacement, the resulting track curves being adapted to the proscribed basic geometry in most cases on a trial and error basis or by insertion of circular arcs. In an attempt to establish new ways of planning, this paper proposes a method for developing the curvature functions that are so important from a dynamic-point of view from a combination not just of the two fundamental factors- lateral acceleration and shock-but also taking account of geometric conditions and desired deflection angle.