Research Idea Details

Research Idea Scope

Problem Statement
The operation of steel-wheeled transit vehicles on steel rails may develop short-pitch corrugation of the rails.
The interaction of the wheels rolling over the corrugated rails generates noise with a tonal component, which is usually harsh and uncomfortable for transit patrons and obtrusive to wayside receivers, and has been associated with the “singing rail” condition. Several variables may contribute to the development of corrugation including rail car suspension components, wheel composition and resonance characteristics, rail metallurgy, tie spacing (both average distance apart and variation), tie composition, tie or rail fixation, roadbed composition, and possibly other unknown elements. Rail corrugation eventually reaches the point where noise exceeds reasonable levels and the nearby community complains. Current practice is to remove rail corrugation by grinding the rail to restore the original profile. On some rail transit properties, a more sophisticated grinding program is followed, which uses multiple profiles to equalize the wear across the wheel tread, and special profiles for curves, which also reduce wheel wear. This program, where rails are ground every 2 to 3 years, reduces corrugation and controls rutting of the wheel tread. However, maintenance costs would be reduced if a design solution or preventive measures besides rail grinding could be found.
 
Proposed ResearchSignificant research into this topic has been conducted and is ongoing elsewhere in the world. A first objective in the United States should be to evaluate the state of research elsewhere and determine its applicability to U.S. needs. U.S. research resources can then be aimed at building on existing research and integrating these efforts towards achieving solutions. In general, this research should be directed towards determining the causative relationships of various design parameters or conditions that contribute to short-pitch rail corrugation. These include track support stiffness, lateral stiffness, damping properties, tie spacing, wheel resonance, rail and wheel metallurgy, and tie characteristics. This substantial effort will result in the development of efficient and effective design approaches and methods for preventing corrugations.