Numerical Simulation of the Composite Bank Stability Process of the Songhua River

Abstract

The phenomenon of bank erosion and collapse is widely distributed in major rivers all over the world, and it is a kind of natural disaster with greater hazards. Bank erosion in seasonally frozen rivers (SFR) is subject to the coupling effects between hydrodynamic forces and freeze-thaw, and the mechanism is complex. Understanding of bank erosion mechanisms is of great significance for river bank protection and comprehensive river management. Taking the downstream near dam section of the Dadingzishan Navigation and Hydropower Project in the mainstream of the Songhua River as an example, the BSTEM model was used to analyze the degrees of riverbank stability in different periods considering the freeze-thaw effect. The results indicated that the degrees of riverbank stability are high during the periods of low water level and water-level rising before the flood season, and the slope toe scour is the main factor; and they are low during the periods of high water level and water-level recession with the continuous bank collapse occurring; The freezing and thawing effect has an important effect on the stability of river banks in the seasonal frozen region. so as to provide a certain reference for the study on the bank collapse of the river in seasonal freezing region and its simulation for the study of riverbank erosion in seasonally frozen rivers.