Effect of snow cover evolution on pore water pressure behaviour in embankments and cut slopes: Field observations

抄録

Snow cover melting leads to a release of stored winter-time precipitation over a relatively short period of time and thus affects the stability of embankment and cut slopes. Capturing the patterns of pore water pressure responses against the snow melt water infiltration and reflecting them into seepage flow analysis and mechanical stability analysis may lead to more precise assessment of the spring-time instability peculiar to snowy cold regions. This paper describes lessons from the authors’ experience in monitoring snow and ground conditions in three sites in Hokkaido, which were with limited access during winter. From long-term observation spanning up to 5 years, patterns and features in the snow cover evolution and ground responses are summarised. A correlation was found between the peak snow cover depth and the delay in slope surface pore water pressure responses, which represents the significant time required for melted snow to travel through the snow beneath. Reflecting this delay could lead to more precise spring-time pore water pressure assessment in slopes.