Dynamic behavior of humid granular avalanches: Optical measurements to characterize the precursor activity

Laboratory study of slope stability of granular media remains a challenge for modeling, understanding, and predicting natural hazards, such as avalanches and landslides, precursory signs of which are controlled by numerous physical parameters. The present work focuses on the impact of the humidity,...

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Detalles Bibliográficos
Autores: Oger, Luc, Tannoury, Claude El, Delannay, Renaud, Le Gonidec, Yves, Ippolito, Irene Paula, Roht, Yanina Lucrecia, Gómez Arriaran, Iñaki
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/168268
Acceso en línea:http://hdl.handle.net/11336/168268
Access Level:acceso abierto
Palabra clave:WET GRANULAR MATERIAL
FLOW INSTABILITY
GRANULAR FLOW
GRANULAR PACKING
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:Laboratory study of slope stability of granular media remains a challenge for modeling, understanding, and predicting natural hazards, such as avalanches and landslides, precursory signs of which are controlled by numerous physical parameters. The present work focuses on the impact of the humidity, in the range of 40-90%, on the stability of monodisperse dense packings of spherical beads. The beads are in a transparent box that is slowly and continuously tilted and allows simultaneous top and lateral optical measurements of global displacements of grains at the surface, defined as precursors. Humidity increases the cohesion between the grains. By performing successive avalanches that destabilize deeper granular layers, we assess the role of the exposure time to the high humidity rates in the diffusion process to reach the hygroscopic equilibrium inside the packing. We highlight an increase of the stability and first precursor angles, associated to a constant angle increment between two consecutive precursors, with a dependency with both the diameter (0.2,0.5, and 0.75 mm) and the material (glass and polystyrene) of the grains.