Numerical simulation of landslide over erodible surface

Abstract

Background: Estimating the magnitude and intensity of landslides is a fundamental requirement in quantitatively evaluating the risks involved, and preparing a mitigation strategy. Though the physics-based dynamic model of landslide can predict the travel distance, kinematic velocity, and hazard zone, the effects of erosion and the excess pore water pressure during the dynamic process of landslide are often ignored. Results: In order to study these factors, a physics-based dynamic model of landslide considering erosion and excess pore water pressure is presented in this paper. A high-precision numerical method based on the finite volume method is proposed to solve the model equations. Several numerical tests are performed to verify the numerical method and the model. The effects of erosion and excess pore water pressure on the dynamic process of landslide are also analyzed. Conclusions: The numerical results indicate that the scale and mobility of a landslide are influenced by the effect of erosion and excess pore water pressure. The excess pore water pressure can reduce the resistance to shear stress from the erodible bed and lead to a higher erosion amount and longer moving distance of the landslide. It also affects the degree of erosion and further affects the dynamic process of the landslide. The sensitivity analysis of the parameters that influence excess pore water pressure indicate that these parameters have a significant impact on the evolution of excess pore water pressure, and that the degree of saturation of bed sediment has the highest influence on excess pore water pressure.

Study on Dynamic Response of Blocking Structure and Debris Flow Impulsive Force considering Material Source Erosion

“…The final debris flow volume after erosion can be as much as 50 times that of the debris flow start volume. The influence of erosion on the volume of the debris flow, impact of the debris flow, and its structure have been verified by numerical simulation and physical simulation experiments done by Haas and Woerkom [14], Liu et al [15], and Tian et al [16]. Shen et al [6], Mangeney et al [12], Haas and Woerkom [14], Mangeney et al [17], and Egashira et al [18] conducted field observations and physical simulation experiments to reproduce the process of detrital flow on soil erosion and systematically study the factors which influenced erosion.…”

“…Shen et al [6], Mangeney et al [12], Haas and Woerkom [14], Mangeney et al [17], and Egashira et al [18] conducted field observations and physical simulation experiments to reproduce the process of detrital flow on soil erosion and systematically study the factors which influenced erosion. Liu et al [15] adopted the finite volume method to simulate the landslide dynamic model considering erosion and excess pore water pressure, while Li and Zhao [19] adopted the CFD-DEM numerical analysis method to study the erosion and mass exchange of debris flow. This research showed that the amount of soil erosion is positively correlated with the slope of the channel and the solid-liquid ratio and also that the fluidity and the impact force of debris flow may increase due to mass exchange.…”

“…A debris flow retaining structure can limit the impact of debris flow fluids and particles and thereby protecting people's lives and property [4]. The effect of impact peak of debris flow must be considered in the design of the debris flow retaining structure [15,19]. Current calculations of the impact of debris flows are generally based on the hydrostatic model, the hydrodynamic model, or the hybrid model [10,[20][21][22].…”

“…Leonardi et al [20,23,24] adopted the LBM-DEM coupled numerical analysis to study the process and impact models of the fluid-particle debris flow mixtures, while the failure mode of the retaining structure was also studied in detail. Liu et al [15] and Li and Zhao [19] adopted the coupled CFD-FEM numerical analysis to study the impact model, the erosion model, and the dynamic response model of the retaining structure of the fluid-particle debris flow mixtures. Here, the model reproduced the dynamic interaction of complex fluid-particle-erosion-structure, and the study concluded that the slope and the solid-liquid ratio are positively correlated with erosion.…”

Impact‐Induced Liquefaction Mechanism of Sandy Silt at Different Saturations

“…e impact-induced liquefaction during the sliding process is probably the driving force behind the high speed and long runout of these landslides on nearhorizontal terraces [2,[19][20][21], but the mechanism of this effect is not yet well understood. Pore water pressure, which plays a crucial role in the liquefaction process, is most affected by the saturation of the soil [22]. erefore, in order to propose a liquefaction mechanism under impact, this paper focuses on the following three research objectives: (1) the development of pore water pressure under impact; (2) the liquefaction characteristics of sandy silt soils under the influence of saturation; and (3) the revealing of the mechanism of impact-induced liquefaction.…”