Torsion-bending-shear interaction for reinforced concrete beams

Abstract

A rational, simple method is presented for analysis of the torsion-bending-shear interaction at failure for reinforced concrete beams. Equilibrium equations are studied for observed failure mechanisms. Three mechanisms can occur depending on where the concrete compression zone is formed: in the top (mode t), in the bottom (mode b), or in one vertical side (mode s). In modes t and b, the torsion-bending and the shear-bending interaction are governed by second-degree parabolas, whereas the torsion-shear interaction is governed by an ellipse. In mode s, the interaction surface is a cylinder with an elliptic base in the torsion-shear plane.Godkänd; 1974; 20061109 (ysko)</p