*2.3. Loading and Boundary Conditions*

The mathematical problem statement is described in Reference [20] and includes equilibrium equations, physical and geometric relations, as well as contact boundary conditions. When realizing the problem, the mathematical formulation was supplemented by considering the possibility of the appearance of large deformations in the EVA. The task was implemented as a 2D problem. The mathematical formulation of the problem was supplemented by boundary conditions: a constant load varying from 50 to 300 N (indentation force) was applied at the boundary Sσ; at the boundary Su, movement along the vertical coordinate *y* was prohibited.
