Research progress on the numerical modelling of two-phase debris flow capturing its super mobility behaviors

Numerical Simulation and Risk Analysis of Landslide Hazard Chains

24 08, 2022

Recently, ANSO Collaborative Research entitled "Numerical simulation and risk analysis of landslide hazard chains in high-mountain Asia considering the effects of global climate change", undertaken by the Institute of Mountain Hazards and Environment, Chinese Academy of Sciences (CAS) has made important progress on the numerical modeling of two-phase debris flows. The major outcomes of the research work have recently been published in Engineering Geology on August 2022.

Due to the impact of global climate change, geological disasters such as debris flows are becoming more frequent in high mountain areas. In this aspect, the super mobility of such multi-phase flows and the mechanisms that drive them are of great research interest. To address the shortcomings of existing debris flow models to accurately capture the flow dynamics, the team of Prof. Gordon G.D. Zhou, with the support of ANSO International Cooperation Project, carried out a series of systematic theoretical analysis with the cooperation of collaborators from the Research Institute for Geo-Hydrological Protection, National Research Council of Italy (IRPI-CNR), Technical University of Munich, Germany, and the International Centre for Integrated Mountain Development (ICIMOD). A depth-averaged continuum model is developed that captures the intrinsic relationship between the solid and fluid stresses within multi-phase flows. This is made possible through the use of state-of-the-art solid-fluid coupling equations and a visco-inertial rheological model for the fluidity of the solid phase. The model is validated against a real debris flow scenario that occurred in the Sichuan-Tibet Railway area. Good agreement between simulated and documented flow and deposition features is achieved showing that the research results are of great significance for the accurate prediction of debris flow disasters.

Citation:

Xie, Y., Zhou, G. D., Cui, K. F., & Lu, X. (2022). Numerical investigation of debris flows using a two-phase continuum model incorporating a visco-inertial rheology. Engineering Geology, 106797.

Source: Xie Yunxu, Institute of Mountain Hazards and Environment (IMHE), Chinese Academy of Sciences

E-mail:xieyunxu@imde.ac.cn

(a) Schematic diagram of a gravity-driven granular-fluid flow down a rough incline.

(b) The influence of the driving forcs with time at specific measurement points.