University of Tennessee Civil and Environmental Engineering Professor Chris Cherry, along with graduate students Ziwen Ling and Nirbesh Dhakal, recently published research in the Journal of Transport & Health on bicycle accidents at a railroad crossing. It is the first study that uses empirical video data to identify factors on detailed crossing and crash processes quantitatively. The data showed 13,247 cyclists traversing two sections of the railway over about two months, with higher than expected crash rates. The crash rate on the shoulder over this period was 15.3 per 1000 crossings, while the crash rate of the greenway (eastbound and westbound) was lower, 2.2 per 1000 crossings.
Factors cover crossing angle, cyclist characteristics, bicycle type, riding behavior, and environmental factors. Crashes are nearly eliminated at crossing angles greater than 30° degrees, and no crashes were observed at crossing angles greater than 60°. In areas with tight design constraints, achieving a 60° crossing angle largely eliminates the problem.
The crossing studied was infeasible to construct at a crossing angle that approached 90°, however, the City of Knoxville responded by constructing a jughandle design with a tangent angle of 57°, with a possible minimum angle of 37° (inside-to-outside of bike lane). This design encourages cyclists to approach this crossing at a higher angle and has effectively eliminated crashes except in cases where cyclists traverse the hash marks and cross at low angles. Future research will further evaluate rider behavior and crash performance under this design.
The Open Access paper is available here: https://doi.org/10.1016/j.jth.2017.01.004
An article about the research was published in City Lab.
A YouTube video documenting the crashes used in the paper (and then some) is available here: https://youtu.be/YfeQvbIFBks
These research findings quickly went viral.