A Synthesis of Railway Concrete Crosstie Advancements in North America

There are over 35 million concrete crossties (sleepers) installed in track in North America, with approximately 750,000 to 1,500,000 additional new ones installed annually. These components have been the focus of much research over recent years, which is resulting in significant advancements in their design and use. New solutions are addressing rail seat deterioration, abrasion, splitting, and other issues that have been associated with past derailments or have required major intervention. Moreover, concrete crosstie design is moving toward a performance-based approach, which is more efficient than the traditional prescription-based methods with generous safety factors. Smart crossties are also emerging, which go far beyond the traditional concepts of crosstie application. This paper presents an overall picture of the state of the art of concrete crossties in North America, linking fundamentals, industry challenges, design approaches, recent developments, and trends for the future.