Improving Inspection of Turnouts

Railway system and track inspection has been the subject of significant research and implementation technology to monitor track conditions and provide timely and accurate information to government agencies, suppliers, and railroads. However, the implementation of new technology is lacking in the area of turnouts and their key components. Turnouts, a design discontinuity in the railroad track structure, represent a change in track geometry as well as in the stiffness of the track structure. High levels of force are generated as a vehicle negotiates the turnout, which results in rapid degradation of the turnout and causes train derailments. Derailments in turnouts represent more than 20 percent of track-caused accidents. While other areas of track structure use the visual and automated inspections required by the Federal Railroad Administration (FRA), turnouts still rely on walking inspections whose key provisions are qualitative rather than quantitative. The National Academy of Sciences (NAS) is sponsoring a project to look at international inspection tools and practices and their potential application for United States freight and passenger railways. While many of these technologies are still in the research, development, or early implementation stages, they represent significant potential for complementing today's visual and manual inspection processes with automated technology in order to provide accurate information about turnout condition.