Estimating the face-to-face reinforcement ratio of short rectangular reinforced concrete columns based on two uniaxial bendings separately

This paper presents a new technique to design RC columns of the rectangular section, subjected to axial compression and uni- or biaxial bending. Distributed bars around the perimeter are considered as an equivalent thin tube. Using the same steel area for two separate couples of axial compression and uniaxial bending is a trick to solve the equilibrium equations for the optimum steel ratio between faces b and h.