Combined method for calculating the total erosion of channels composed of easily erodible grounds

Abstract

Abstract Riverbed processes on rivers composed of easily eroded soils differ in intensity. Therefore, deformation calculation methods are needed that take into account the characteristic features of such rivers. These features can be taken into account by introducing into the composition of the initial equations of dependencies reflecting the features of the alluvial regime and the nature of deformations. To this end, based on the analysis of existing empirical dependencies and actual data of the total erosion below the Takhiatash hydro unite (Amu Darya River, Uzbekistan), the structure and type of dependence of the transporting capacity of the stream on the main parameters of the channel and the morphometric dependence of the width of the stable channel on the average depth were selected. The proposed combined calculation method is based on the theoretical equations of deformation (Saint-Venant) and the equation of fluid motion (Bernoulli) and empirical dependencies for determining the average turbidity of the flow and the width of the channel. With the use of these equations, the calculation of the total erosion below the Takhiatash hydrounite on the Amu Darya River was carried out. Comparison of the calculation results and the actual data showed their satisfactory convergence. The proposed method can be applied to calculate channel deformations on rivers composed of easily eroded soils when regulating the flow of retaining structures.