The results of investigations of stress-strain state of the foundation for the vertical steel tank with sequential action loads in the construction and operation. Developed three-dimensional numerical model studies that take into account the physical nonlinearity and allows successive loading method to evaluate the stress-strain state of the tank foundation at each step of loading. Regularities of the change of the stress-strain state of the tank Foundation and subgrade in the modeling of the process of construction of the tank and fill the oil during operation. The dependences of maximum stresses from deformation modulus of concrete and soil deformation modulus.

Keywords: foundations, tank, soil stress-strain state, filling volume model, the successive loading step method, module of deformation