METHOD OF CALCULATING STRESS-STRAIN STATE AND SOIL COMPACTION DURING OPERATION AND AFTER STOPPING THE WHEEL TRACTOR
Based on the results of theoretical studies and field tests it was solved the mathematical modeling of the processes of deformation and soil compaction during the work and after stopping wheel tractor. The effect of soil load taking into account the viscoelastic properties of the soil are described by differential equation of the first order connecting the compressive stresses, the rate of change of compressive stress and relative deformation of compression. Considered viscoelastic properties of sward-podzolic light loamy soil identified in field tests. Based on the results of the statistical processing experimental data the dependence on depth the density of the soil before the impacts on soil external loads adopted quadratic. Performed computer experiments in which the indicators, allowing to estimate quantitatively the changes in strains, stresses in the soil and density of soil during the work of tractor and creep of the soil after stopping the tractor. Obtained correlation dependencies of these indicators from time, density, and soil moisture, the speed of its initial deformation. The proposed calculation method allows to find the indicators at different depths of a deformable soil layer, and a stabilization time of soil deformation.