Development of the reinforced concrete resistance theory in the zone about reinforcement

Abstract

The actual problem of resistance of near-reinforcement zone of concrete is solved as a problem of volumetric stress-strain state with "closure" of output integral parameters of this zone on the rod scheme of the whole reinforced concrete element synthesizing hypotheses and dependencies of various disciplines of mechanics of solid deformation body, including fracture mechanics. The calculation model of the reinforced concrete element takes into account the effect of reinforced concrete of prof. Vl.I. Kolchunov describing the mechanism of formation and development of transverse and longitudinal cracks. In this case, generalized hypotheses of linear and angular deformations for warping and gradients of jumps of relative mutual displacements of reinforcement and concrete are adopted. New functionals of reinforced concrete are constructed, which are consistent with the ideas about resistance of crosssections of rod elements in near-reinforcement zones. Physical equations for a concrete matrix modeled between transverse cracks are written. The displacement components for the near-reinforcement area are found in relation to the crack opening width at the boundary of the "concrete-reinforcement" contact in transverse, longitudinal and radial cracks, respectively. The use of the accepted assumptions and multi-level calculation scheme for the near-reinforcement region significantly brings the calculation model closer to a real assessment of physical phenomena.