In this study, the failure behaviors of debris flows were studied by flume model tests with artificial rainfall and numerical simulations (PFC(3D)). Model tests revealed that grain sizes distribution had profound effects on failure mode, and the failure in slope of medium sand started with cracks at crest and took the form of retrogressive toe sliding failure. With the increase of fine particle...

Bridge clogging due to a debris flow is phenomenon scarcely studied but critical in hazard mapping the mountain area. Since rational and systematic approach still missing, we propose practical method deal with this numerical framework. We tested methodology by using, as model, two-phase, mobile-bed model TRENT2D and, site test case, village of Voueces north-west part Italian Alps. The applicati...

In Japan, many debris flows and sediment-laden floods cause serious damage to human life property. Effective measures require high-accuracy reproduction prediction of runout distance (bed variation reach) via numerical simulations. One possible method increase the accuracy simulation results involves reviewing methods used evaluate depositing rate for that contain different sizes sediments. Thi...

Stony debris flow transits to sediment sheet when the river bed gradient becomes gentle. The consists of a water layer and moving layer. Fine sediments are expected behave as part fluid rather than solid phase in Further, it can be thought that fine suspended However, was not possible physically express whether behaves or numerical simulation model. Here we modeled behavior flow. We confirmed a...

Automatic identification of debris flow signals in continuous seismic records remains a challenge. To tackle this problem, we use machine learning, which can be applied to real-time data. We show that learning model based on the random forest algorithm recognizes different stages formation and propagation at Illgraben torrent, Switzerland, with an accuracy exceeding 90 %. In contrast typical de...