Theoretical basis for design of load-bearing structures produced using additive technologies

The article discusses interconnections and mutual influence between the triad of the basic engineering concepts - material, technology and structure. The possibilities for development of load-bearing structures, produced using additive technologies are analyzed. The task of optimal material distribution within a body of variable density is formulated and solved. An algorithm for topologic optimization of load-bearing structures, produced form a material of variable density, based on the criteria of minimal mass is proposed. General mechanical properties of the hypothetical material are assumed to be proportional to its density. The limitations of strength and rigidity are considered for single and multiple loading cases. The content of the concepts "optimal" and "rational" structure is discussed and refined. The "force factor" objective criterion, which takes into account the magnitude and extent of the action of internal forces, is proposed as a measure of comparison of the weight perfection of various designs and to estimate the design proximity to a theoretically optimal solution. The article presents examples of two and three dimensional structures. Future goals are formulated to develop new materials and methods for creating structures with variable density as one of the possible directions for the further development of additive technologies.