Influence of Material Structural Inhomogeneity on Fracture Strength of Constructional Elements

摘要

The issue of material and construction fracture is one of unresolved problems in mechanics. The phenomenological approach used by mechanics of softening materials is taken by the authors for the purposes of solving that problem. Deformation of the "machine - model specimen" system is analyzed in the article using catastrophe theory for various boundary conditions. Computer simulations using a material's calculation model allowed to establish nonlocal character of fracture criteria and correlation between static and cyclic properties of the model material. It is shown that the fracture scenario for a mechanical system depends on the degree of structural inhomogeneity of the material and the loading conditions. Regarding the fracture as a loss of deformation stability leads to a new understanding of the mechanical system's ultimate state. The obtained results could be used to improve methodologies for calculating life and durability of constructions.