2024 年 65 巻 4 号 p. 245-251
Volcanic ash fall can seriously affect railway operations by causing problems such as track circuit shunting malfunctions and decrease in insulation performance of insulators. In this study, we experimentally investigated volcanic ash conditions that cause these problems. Results allowed us to clarify that 0.05 mm thick volcanic ash causes shunting malfunction, and that 1.2 mm thick volcanic ash containing saline water causes insulator flashover. Based on these results, we propose preventive actions which railway companies can implement to mitigate the effects of ash fall, using public information on eruptions.