Abstract
This report focuses on the road damage caused by the earthquake that occurred in the Noto
region of Ishikawa Prefecture on January 1, 2024. Looking at the causes of damage by route, the
main cause of damage for Noto Satoyama kaido and Noetsu Expressway was road damage due
to embankment collapse. On the other hand, along National Route 249 and Prefectural Route 38,
which run along the coast, there were many spots where slope failure was a contributing factor.
The average maximum inclination angle at points where slope failure was the cause was
approximately 32.6 degrees, while at points with road surface damage there was a difference of
approximately 18.5 degrees. Furthermore, regarding the difference in elevation between the
center of the road and the road shoulder, the site of the slope failure is estimated to be on a slope
approximately 20m higher than the center of the road, while the road surface damage is
estimated to be in the shape of an embankment of approximately 10m. As a result of attempting
to interpret the stream topography using contour line interpretation, it became clear that all of
the points were those related to stream topography or convex parts of the contour lines.
