Optimal design of shape and reinforcement for concrete sections

This document presents a procedure for the optimal design of reinforced concrete sections of general shapes subject to a biaxial bending. The optimal design problem is formulated as a non-linear mathematical programming problem. The problem is formulated so that time-consuming searches for the precise location of the neutral axis are avoided through intermediate steps of the optimization process. There are three kinds of design variables: geometry variables, reinforcement variables and location of the neutral axis variables. The objective function is the cost of a structural member per unit length. There are three kinds of constraints: strength constraints, minimal amount of steel constraints and bound constraints