Reinforcement sizing diagrams for concrete beams and columns

Abstract

A new diagram for determining acceptable quantities of reinforcement for reinfoced and prestressed concrete members subjected to combined flexural and axial loads is presented. The ?reinforcement sizing diagram? (RSD) provides a graphical representation of the complete solution of acceptable reinforcement combinations to satisfy specified combinations of factored moment and axial load. Knowledge of the entire range of acceptable solutions provides a basis for the design engineer to select a specific combination of tension and compression reinforcement to be used. Reinforcement may be optimized to be requiered for convenience in construction. The construction of the RSD makes use of numerical procedures readily available in common software packages for the solution of the nonlinear system of equations of equilibrium over a continuous range of values of the depth of the neutral axis. Several examples are presented.