MODEL AND METHOD FOR CALCULATING THE RESOURCE OF REINFORCED CONCRETE ELEMENTS AND STRUCTURES

Abstract

Abstract. The article classifies, identifies and analyzes in detail the main disadvantages of existing models and methods for calculating the resource of building structure elements. A universal model and method for calculating the general and residual resources of reinforced concrete elements and structures that are under prolonged influence to operational loads are proposed. The generalized deformation-force model of the reinforced concrete elements and structures resistance to force effects is represented by an extended system of equations of the deformable solid mechanics. It is shown that the most important force and deformation parameters of the reinforced concrete elements state diagrams at all stages are functionally interconnected not only by rigidity, but by the potential energy of deformation. Therefore, due to the application of the hypothesis of invariability in a unit of volume and independence from the loading mode of the potential energy of their limiting deformation, this model has been developed to the energy level. The main advantages of the developed model of the reinforced concrete elements to force effects resistance in comparison with the existing force and deformation models in determining the resource of such elements are demonstrated. The methodology for calculating the general and residual life of reinforced concrete elements and structures is proposed to be built according to the deflections directly measured during field surveys or the step and width of the opening of normal cracks. In practice, they can be determined by geodetic, photogrammetric or any other means. The combination of the deformation-force model and the energy criterion makes it possible to calculate the general and residual resources of reinforced concrete elements and structures from a unified methodological standpoint. Therefore, the proposed "energy" hypothesis is recommended to be used as a universal energy criterion not only for the bearing strength exhaustion of the reinforced concrete elements, but also for limiting their deflections, as well as the width of the normal cracks opening under the action of any duration loads.