Representative volume of characteristic zones of the stressstrain state in the mechanics of reinforced concrete

The article presents tools for creating computational models of reinforced concrete resistance based on the concepts of "representative volume" and "characteristic zone". The tools are based on the idea of modeling zones of a structure characteristic of the type of stress state in the form of a composite strip-prism, which are described by a volume representative of the considered type of stress state, including under load-varying force flows due to crack opening-closing, shear cracks, changes in distances between main cracks, and, accordingly, changes in the stiffness of the representative volume along the three axes.

The proposed model allows determining the resistance of a reinforced concrete structure with various types of stress states in characteristic zones of the deformable space, considering the type of concrete, reinforcement classes, and specific weights of their areas, as well as considering the deformation effect during crack opening established by the author based on the fracture mechanics functional using a double-cantilever element (DCE).

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