2023 Volume 38 Issue 2 Article ID: 38.115
We investigated the suitability of six routes for access to ten-ton (10-t) class logging trucks in a rural forest management area located in the Kochi Prefecture. The width of roads, measured on site, was checked against images held on a drive recorder. The radii of the road curves were estimated using interpolation algorithms available in a Geographic Information System application. Necessary road width expansion was calculated by the difference between the actual road width and the width of the Type II Class 2 forest road (3.0 m) added to the extent of widening required for the curve radius. One of the existing routes, which was ascertained to be unsuitable for 10-t class trucks, was found to have significantly lesser necessary expansions to road width, implying that it was originally constructed for lighter 4-t class vehicles. The other routes investigated, including a purpose-built forest road and an upgraded forest road as a prefectural road, were found to be sufficiently wide for accommodating 10-t trucks, although certain sections were significantly narrow in residential areas.