Print Email Facebook Twitter Quantification of the influence of preferential flow on slope stability using a numerical modelling approach Title Quantification of the influence of preferential flow on slope stability using a numerical modelling approach Author Shao, W. Bogaard, T.A. Bakker, M. Greco, R. Faculty Civil Engineering and Geosciences Department Water Management Date 2015-05-07 Abstract The effect of preferential flow on the stability of landslides is studied through numerical simulation of two types of rainfall events on a hypothetical hillslope. A model is developed that consists of two parts. The first part is a model for combined saturated/unsaturated subsurface flow and is used to compute the spatial and temporal water pressure response to rainfall. Preferential flow is simulated with a dual-permeability continuum model consisting of a matrix domain coupled to a preferential flow domain. The second part is a soil mechanics model and is used to compute the spatial and temporal distribution of the local factor of safety based on the water pressure distribution computed with the subsurface flow model. Two types of rainfall events were considered: long-duration, low-intensity rainfall, and short-duration, high-intensity rainfall. The effect of preferential flow on slope stability is assessed through comparison of the failure area when subsurface flow is simulated with the dual-permeability model as compared to a single-permeability model (no preferential flow). For the low-intensity rainfall case, preferential flow has a positive effect on drainage of the hillslope resulting in a smaller failure area. For the high-intensity rainfall case, preferential flow has a negative effect on the slope stability as the majority of rainfall infiltrates into the preferential flow domain when rainfall intensity exceeds the infiltration capacity of the matrix domain, resulting in larger water pressure and a larger failure area. Subject OA-Fund TU Delft To reference this document use: http://resolver.tudelft.nl/uuid:2afb11ea-f993-495e-858f-d4a95e9e2143 DOI https://doi.org/10.5194/hess-19-2197-2015 Publisher European Geosciences Union (EGU) ISSN 1027-5606 Source http://www.hydrol-earth-syst-sci.net/19/2197/2015/ Source Hydrology and Earth System Sciences, 19 (5), 2015 Part of collection Institutional Repository Document type journal article Rights © 2015 The Author(s)CC Attribution 3.0 License Files PDF Shao_2015.pdf 3.15 MB Close viewer /islandora/object/uuid:2afb11ea-f993-495e-858f-d4a95e9e2143/datastream/OBJ/view