The Transformation of Technological Cracks into Operational Ones

It is known that, regardless of the mechanisms occurring at various levels, what is common to the composite system is the formation of internal interfaces that can transform into cracks. Such cracks are classified as technological cracks, which are present in the sample material before operational loads are applied to them. Of greatest interest is the distribution of shrinkage strains in materials with a network of technological cracks and their effect on the deformability of concrete and on resistance under low-cycle fatigue loading. It is emphasized that the formation and development of technological cracks is determined by technological cracks. This made it possible to qualitatively assess the change in damage to structures and propose a methodology that takes into account the deformation of concrete containing technological and operational cracks in its structure. It is important to study the mechanism of initiation and development of initial cracks under the action of alternating loads, the mechanism of fatigue growth of technological cracks under alternating volumetric deformations of swelling and during a cycle of decreasing the volume of the material, as well as under the action of varying amounts of shrinkage deformations on its banks. Therefore, the study of the transformation of technological cracks into operational ones under the action of low-cycle loads in concrete and reinforced concrete is of particular relevance.