Space grid structures are widely used for covering large-span public and industrial buildings and allow for a wide variety of structural and architectural forms. The article presents and solves the problem of finding a design solution for a space grid coating structure of minimum mass for a given steel class, element cross-section type, and loading conditions. The location of the supports is considered as a variable parameter, which leads to a different stress-strain state of the structure, and, accordingly, different cross-sections of the supporting elements.The change in the stress-strain state of the roof space structure when changing the location of the supports was studied. In total, 10 options for the arrangement of supports of a space structure with a size of 24x24 m and 7 options for a space structure with a size of 30x30 m were considered. After the load was applied, the VAT of the structure was determined numerically, the cross-section of the elements was selected and their mass was calculated. Then a comparison of the various options for supporting by the weight of the structure was made. In the article, the optimization problem was solved according to the optimality criterion of metal consumption, restrictions in the form of overall dimensions, topology and strength conditions.

Keywords: space grid structures, optimization, metal consumption, control parameter

The article is devoted to the task of searching for the design solution of the structural coating plate. Structural plates are widely used to cover single-storey structures and have a wide variety of structural and architectural forms. The choice of minimum weight design is based on the VAT control method. As the regulators adopted the location of the columns and the class of steel. Depending on the number and location of the columns on which the structural plate rests, the forces in the structural elements change and accordingly the cross-sectional area and mass of the structure change. Four variants of the arrangement of the columns and three versions of the class of steel were considered. For each design variant, the design was calculated numerically, the cross-section was selected, and the mass was determined. Based on the accepted criterion of the effectiveness of the design solution - metal consumption, the most effective design solution was adopted with the arrangement of columns along the perimeter of the coating in steps of one cell.

Keywords: space grid structures for roofs, regulation of stresses, optimization, metal consumption, criterion of optimality

Possibilities of using mathematical programming methods for obtaining optimal solutions of structural units were shown herein. Method of personal optimization based on monotonicity property of the used relations was applied as optimization algorithm. Advisability of using mathematical simulation methods when providing complex safety of construction facilities and reduction of breakdown occurrence is emphasized.

Keywords: optimal design, mathematical simulation, complex safety, personal optimization, plate structures, risk.