THE CALCULATION MODELS OF STATIC AND DYNAMIC DEFORMATION REINFORCED CONCRETE CONSTRUCTIONS IN TORSION WITH BENDING AT THE time of the spatial crack formation

Abstract

The article proposes to introduce static-dynamic model of the second level deformation in a complex stress-strain state torsion with bending at the time of spatial crack formation. These models take into account impulse action in the form of representative volumes of concrete cut from the reinforced concrete structure in the vicinity adjacent to the spatial crack of concrete prisms including the reinforcing bar and subject to central tensile with shear. In this case, the influence of internal stresses takes into account integrally, not directly, in cross-sections which have taken for cutting of the proposed second level models, through a specially-constructed first-level computational model. This first- level model simulates spatial section with internal forces arising in it, i.e. this influence is evident in a representative volume through such parameters as the distance between the spatial cracks, the stress in the working reinforcement of the investigated zone in second stage, and also in the determination of the main (or normal and shear stresses, depending on the cross-section has made) deformation (stresses) of concrete and deformation (stresses) of the reinforcing rod entering to the representative volume, which adjacent to the surface of another simulated not appeared spatial crack in stage Ia. The basic working hypotheses are given. Dependences were obtained for determining the stresses in the stretched reinforcement that would have arisen in this system if the n-system transition to the system (n-1) as a result of instant destruction of a section of the section k.