Evaluation test of tangential force coefficient under different types of fallen leaves

Abstract

On railway lines in mountainous areas, wheel slip and wheel slide frequently occurr due to a decrease in adhesion coefficient caused by fallen leaves in wet conditions. One of the countermeasure is tree felling, and knowing which tree species significantly reduce the adhesion coefficient is helpful in determining the order of priority for felling. In this study, the tangential force coefficient, which is strongly correlated with the adhesion coefficient and the maximum tangential force coefficient is generally defined as the adhesion coefficient, was quantitatively assessed for fallen leaves of five tree species using a rolling-slip friction measurement machine. The experimental results showed that the tangential force coefficients in order of lowest to highest belong to ginkgo, cedar, cherry, maple, and zelkova in wet conditons. This experiment identified which tree species are more slippery and have a high priority for felling.