Publications

2018

• Multiphase smoothed particle hydrodynamics approach for modeling soil–water interactions
  
  • Krimi Abdelkader
  • Khelladi Sofiane
  • Nogueira Xesús
  • Deligant Michael
  • Ata Riadh
  • Rezoug Mehdi
  Advances in Water Resources, Elsevier, 2018, 121, pp.189-205. In this work, a weakly compressible smoothed particle hydrodynamics (WCSPH) multiphase model is developed. The model is able to deal with soil-water interactions coupled in a strong and natural form. A Regularized Bingham Plastic constitutive law including a pressure-dependent Mohr-Coulomb yield criterion (RBPMC-αμ) is proposed to model fluids, soils and their interaction. Since the proposed rheology model is pressure-sensitive, we propose a multiphase diffusive term to reduce the spurious pressure resulting from the weakly compressible flow hypothesis. Several numerical benchmarks are investigated to assess the robustness and accuracy of the proposed multiphase SPH model. (10.1016/j.advwatres.2018.08.004)
  DOI : 10.1016/j.advwatres.2018.08.004
• Transport of moderately sorted gravel at low bed shear stresses: The role of fine sediment infiltration
  
  • Perret E.
  • Berni Céline
  • Camenen B.
  • Herrero A.
  • El Kadi Abderrezzak K.
  Earth Surface Processes and Landforms, Wiley, 2018, 43 (7), pp.1416-1430. A reliable estimation of sediment transport in gravel-bed streams is important for various practical engineering and biological studies (e.g., channel stability design, bed degradation/aggradation, restoration of spawning habitat). In the present work, we report original laboratory experiments investigating the transport of gravel particles at low bed shear stresses. The laboratory tests were conducted under unsteady flow conditions inducing low bed shear stresses, with detailed monitoring of the bed topography using a laser scanner. Effects of bed surface arrangements were documented by testing loose and packed bed configurations. Effects of fine sediments were examined by testing beds with sand, artificial fine sand or cohesive silt infiltrated in the gravel matrix. Analysis of the experimental data revealed that the transport of gravel particles depends upon the bed arrangement, the bed material properties (e.g., size and shape, consolidation index, permeability) and the concentration of fine sediments within the surface layer of moving grains. This concentration is directly related to the distribution of fine particles within the gravel matrix (i.e., bottom-up infiltration or bridging) and their transport mode (i.e., bedload or suspended load). Compared to loose beds, the mobility of gravel is reduced for packed beds and for beds clogged from the bottom up with cohesive fine sediments; in both cases, the bed shear stress for gravel entrainment increases by about 12%. On the other hand, the mobility of gravel increases significantly (bed shear stress for particle motion decreasing up to 40%) for beds clogged at the surface by non-cohesive sand particles. (10.1002/esp.4322)
  DOI : 10.1002/esp.4322