Dynamic modelling of entrainment in rapid landslides

• Published in: Canadian geotechnical journal Vol. 42; no. 5; pp. 1437 - 1448
• Main Authors: McDougall, Scott, Hungr, Oldrich
• Format: Journal Article
• Language: English
• Published: Ottawa, Canada NRC Research Press 01.10.2005; National Research Council of Canada; Canadian Science Publishing NRC Research Press
• Subjects: Algorithms; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Engineering geology; Entrainment; Exact sciences and technology; Geophysics; Landslides; Landslides & mudslides; Momentum transfer; Rheology; Rocky Mountains; rivers; algorithms; models; mobility; rheology; terrains; simulation; North America; avalanches; materials; displacements; landslides; erosion; tellurium; debris; growth; computers
• ISSN: 0008-3674; 1208-6010
• DOI: 10.1139/t05-064

Entrainment of path material is an important feature of many rapid landslides. The associated increases in volume and changes in flow character can significantly influence mobility. A simple material entrainment algorithm, based on the assumption of natural exponential growth with displacement, has been incorporated into a new computer model designed to simulate rapid landslide motion across 3D terrain. The user controls the growth rate and can also implement a change in rheology at the onset of entrainment. A hypothetical example is used to demonstrate the influence of the mass and momentum transfer assumptions. A back-analysis of the 1999 Nomash River landslide is included to show that the simple model is capable of simulating the bulk characteristics of a complex event involving substantial entrainment.Key words: landslides, debris flows, rock avalanches, entrainment, erosion, dynamic modelling.