Оценка значений прочностных характеристик грунта при нелинейной зависимости его сопротивления сдвигу от нормального давления

When studying the transport-shear mudflow, riverbed washouts, the stability of landslide slopes, when designing buildings and structures, including hydraulic engineering, it is important to assess the parameters of the strength properties of soils. To determine these parameters according to the requirements of all the main regulatory documents, it is necessary to use the linear Coulomb equation , characterizing the relationship between the normal pressure on the soil σ and its shear resistance τ. However, as numerous experimental studies show, this dependence is nonlinear, especially in the region of low pressures (< 0.1 MРa), and can be approximated by a power function of the form . In the case of using a linear relationship between shear resistance and normal pressure, the angle of internal friction φ and the specific soil adhesion c are simply determined and are constants under any load. In the case of using a power dependence, difficulties arise with their assessment. In order to match the approximation of the results of the soil shear study by a nonlinear function to the existing regulatory framework, we assume that the state of the soil at a given normal pressure σ₀ is sufficiently described by the tangent equation at points with a certain normal pressure σ₀. The derivative of the function at the point σ_i is equal to the tangent of the angle of inclination of the tangent drawn to the graph of the function at this point. Therefore, the tangent of the angle of internal friction at the point σ_i will be equal to the first derivative of the power function at this point.