HYDRODYNAMICS AND ACOUSTICS

2018 ◊ Volume 1 (91) ◊ Issue 3 ◊ p. 302-315

I. M. Gorban^*, A. S. Kotelnikova^*, V. I. Nikishov^*, G. P. Sokolovsky^*

^* Institute of Hydromechanics of NAS of Ukraine, Kyiv, Ukraine

Formation of the slope angle of the cohesionless soil in a two-dimensional case

Gidrodin. akust. 2018, 1(3):302-315

https://doi.org/10.15407/jha2018.03.302

TEXT LANGUAGE: Russian

ABSTRACT

It is impossible to reduce the risks associated with landslide processes, collapses and other negative consequences of intensive construction in the coastal zone, as well as the uncontrolled collection of water and sand without understanding the physics of the destruction of granular media. At the same time, the quantitative characteristics of such processes remain understudied. For this reason, the paper presents the results of the model experimental studies related to the formation of the inclination angle of the cohesionless soil in the two-dimensional case. The process of formation of the repose angle in the destruction of a granular column in air and water, as well as at bottom erosion is considered. In all cases the angles formed during the destruction of the granular column are found to be close to the natural angle of repose for this type of soil. In this case, the form of the deposit profile depends practically only on the coefficient of proportionality, which is defined as the ratio of the initial height to the horizontal size of the column. It is shown that the formation of the repose angles is associated with the process of the bottom surface erosion. In the formation of the erosion crater of a triangular profile with steep slopes, irrespective of the intensity of absorption of soil particles and the coefficient of proportionality, the angle of inclination of generatrix of the crater's intrinsic surface to the horizon is found to be equal to the angle formed by sand column destruction in water. The obtained data may be useful for predicting the limiting angle of repose in the development of channel quarries for sand extraction, since the shape of the longitudinal profile of the slope determines the nature, course and correlation of the processes of erosion and accumulation.

KEY WORDS

granular flow, unconnected soils, sand column, collapse, natural angle of repose, erosion pool, coefficient of proportionality

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