Status: this discussion paper is a preprint. It has been under review for the journal Natural Hazards and Earth System Sciences (NHESS). The manuscript was not accepted for further review after discussion.
Model development for simulating mudslide and the case study of the failure of the gypsum tailings dam in East Texas in 1966
Tso-Ren Wu,Thi-Hong-Nhi Vuong,Chun-Yu Wang,Chia-Ren Chu,and Chun-Wei Lin
Abstract. Mudslides, avalanches, and mine dam-breaks can be serious disasters and cause severe damages but the detailed flow field description has not been completed yet. This paper developed a modified Bi-viscosity model (MBM) to solve the mudslide flow by adopting Bingham model (BM) and the conventional Bi-viscosity model (CBM). In both CBM and MBM, a yield strain rate is used to identify the plug and liquefied rheological prosperities. In the MBM, an extremely high plug viscosity adopted to represent the stratification effect. BM, CBM, and MBM are integrated into the Splash3D model, which solves Navier-Stokes equations with PLIC-VOF surface-tracking algorithm. The viscosity term is solved by implicit iteration. The model is carefully validated with theoretical results and laboratory data with good agreements. The Splash3D model is then used to study the failure of the gypsum tailings dam in East Texas in 1966, briefed as FGT66. A series of sensitivity analyses on the yield strain rate and grid resolution is performed. The results show that the predicted flood distance and flood speed by MBM is very close to the field data. The MBM results illustrate the process that the plug zone and liquefied zone is developed. The simulations show the initiation of the mudslide flow, the development of the slip surface, the flooding process, and the velocity ceasing process. The slip surface is developed automatically without empirical equations. By comparing the results of BM, CBM, and MBM to the field data, we conclude that the liquefied tailings are under the effect of stratification, and the stratification effect is presented in the extremely high plug viscosity in the Splash3D model.
How to cite. Wu, T.-R., Vuong, T.-H.-N., Wang, C.-Y., Chu, C.-R., and Lin, C.-W.: Model development for simulating mudslide and the case study of the failure of the gypsum tailings dam in East Texas in 1966, Nat. Hazards Earth Syst. Sci. Discuss. [preprint], https://doi.org/10.5194/nhess-2020-126, 2020.
Received: 17 Apr 2020 – Discussion started: 02 Jun 2020
Many studies concentrate on mudflow; however, the stratification between the solid and liquid phase inside the mud material has been not considered. This study provides a modified Bi-viscosity model (MBM) to describe the mudslide flow with the stratification effect. The MBM can simulate the initiation of the mudslide, then the development of the slip surface, the flooding process, the velocity ceasing process, and the stoppage of mudflow.
Many studies concentrate on mudflow; however, the stratification between the solid and liquid...