This article provides the design of the tower shallow foundations using numerical simulation in the "Midas GTS NX" software. The foundations are four separate structures that perceive the bearing reactions from the tower supports. Depending on the wind load direction, the support reactions change both quantitatively and qualitatively. So, one foundation can accept a compressive force, the other one can accept a pull-out force. In this study, two variants of wind loading are considered: the wind load acts on the tower face or on the tower edge. The geological conditions of the research site are taken as simplified. The soil base consists of one engineering-geological element, which is a loess soil. Numerical simulation of the soil massif was implemented by using volumetric finite elements. An elastic-plastic deformation law and a Mohr–Coulomb failure criterion were applied for these finite elements. The design provided for the calculation of the tower foundation on a natural basis and with the arrangement of a compacted sub-base. Research was carried out for the foundations of the tower construction in four stages: 1) soil base in its natural state; 2) arranged compacted sub-base; 3) natural basis with local water saturation of the soil; 4) compacted sub-base with local water saturation of the soil massif. Simulation of the arrangement of the compacted sub-base occurs by replacing the stiffness of the finite element at a certain stage of the calculation. The soil water saturation simulation algorithm is performed in a similar way - there is a change in the physical and mechanical characteristics of certain finite elements. The localization of saturation zones was chosen from the conditions of the most unfavorable combinations of loads and vertical movements of the foundations. An analysis of the stress-strain state of the soil base of foundations under the tower on a natural base and with the arrangement of a compacted sub-base was performed. The scheme of the applied load on the foundation and the possible local water saturation of the loess soil at the base of the foundations were taken into account
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