Design of optimum cross-sections for load-carrying members using multi-objective evolutionary algorithms

Abstract

To reduce the induced undesired stresses, a powder transmitting shaft or a load carrying beam should have its related area moment of inertia as large as possible. Similarly, to avoid early buckling and hence, to increase the capacity, a compressive load carrying strut should have a radius of gyration as large as possible. As the radius of gyration is directly proportional to the square root of area moment of inertia, a strut also should have its related area moment of inertia as large as possible. However, an increase in such moment of intertias comes with an increase in the transverse cross-sectional areas and hence, the weight of the members. Therefore, the maximization of moment of inertias should not take place at the cost of excessive weights of the members. Attempt has been made here to design optimum cross-sections for such load-carrying members, using a multi-objective evolutionary algorithm, for simultaneously maximizing moment of inertias and minimizing the cross-sectional areas. The succrss of the work has been shown through a few case studies.