ОЦЕНКА ЛИНЕЙНЫХ РАЗМЕРОВ АГРЕГАТОВ СВЯЗНОГО ГРУНТА ПРИ РАЗМЫВЕ

For cohesive soils, which include clay, clayey and sandy loam soils, a structure is characteristic in which aggregates occupy an significant place. Since the aggregates are presumably completely washed away by the water flow, a correct assessment of their strength and linear dimensions will make it possible to make physically based calculations of bottom erosion, including culverts, drainage engineering structures of forest roads and meliorative channels. An approach developed by the authors to assess the value of soil adhesion based on measuring the linear dimensions and density of aggregates of cohesive soil is presented. As an example, calculations of the sizes of aggregates of sandy loam of various cohesive soils of quaternary ground horizons of the Priilmenskaya lowland, such as red-brown, spotted, burgundy and blue-gray dense sandy loams are presented. The simplest of the densest packages of aggregates in the soil body – hexagonal and cubic – are considered. As a working hypothesis, the assumption was made that the mutual arrangement of the aggregates is in a hexagonal close-packed lattice. A comparative analysis of the results of averaged measurements and the calculated values of the linear dimensions of the aggregates according to the proposed method and the method set out in SP 32-102-95, showed that the direct linear relationship between the value of soil cohesion and the dimensions of the aggregates given in the current regulatory document does not correspond to empirical data. With a decrease in the density of the soil, its cohesion decreases, the sizes of aggregates for most cohesive soils increase, while their strength decreases, in the future, they are destroyed into smaller and more stable ones.