Riverbank Stability Assessment under River Water Level Changes and Hydraulic Erosion

Toan Duong Thi,Duc Do Minh

doi:10.3390/w11122598

Abstract

The dominant mechanism of riverbank cantilever failure is soil erosion of the bank toe and near bank zone. This paper demonstrates that the shape of the riverbank cantilever failure depends on the properties of the soil and the fluctuation of the river water level (RWL). With a stable RWL, a riverbank with higher resistance force leads to failure with larger and deeper overhang erosion width. When RWL rises, a less cohesive soil bank will be eroded over a larger width and riverbank failure will occur earlier. With a low rate of rising RWL, riverbank failure may happen in a type of mass failure. With a high rate of rising RWL, a riverbank will fail in a type of overhang riverbank failure, with the soil erosion rate being the main affected factor.

Highlights

Riverbank failure occurs by multiple factors, especially during a rainy season, such as the fluctuation of river water level (RWL), groundwater, pore water pressure, soil strength, and soil erosion
The role of the related factors in mass failure mechanics have been studied quite clearly in [2,3,4,5,6,7,8,9], which found that the relationship between the soil hydraulic and the rate of RWL change is the main factor controlling these factors as well as the riverbank stability
Soil erosion occurs when the water shear stress caused by water flow around the interface of water and soil is higher than the critical shear stress [44]

Summary

Introduction

Riverbank failure occurs by multiple factors, especially during a rainy season, such as the fluctuation of river water level (RWL), groundwater, pore water pressure, soil strength (soil suction and shear strength), and soil erosion. The role of the related factors in mass failure mechanics have been studied quite clearly in [2,3,4,5,6,7,8,9], which found that the relationship between the soil hydraulic and the rate of RWL change is the main factor controlling these factors as well as the riverbank stability. The river water level increases and flows with a high shear stress, expanding the soil erosion width and creating an overhanging riverbank shape

Methods

Results

Conclusion