Optimal Design of Truss Structures with Natural Frequency Constraints Utilizing IWSA Algorithm

Abstract

Constructing structures with the lowest possible use of the material has long been an interesting topic among engineers. In this regard, the resilience of structures in the face of natural hazards and their concomitant effects, such as the resonance phenomenon, should also be taken into account. Frequency-constrained optimization problems seek to not only construct structures with the least possible material amount, but also prevent the resonance phenomenon, enhancing the sustainability of the structures by reducing the total material consumption while minimizing the future damage cost incurred by structural components due to this effect. This article assesses the truss optimization problems with natural frequency constraints using the improved version of the newly developed meta-heuristic algorithm, referred to as the water strider algorithm (WSA). Improved water strider algorithm (IWSA) utilizes two mechanisms to improve the performance of WSA. The first one is the opposition-based learning (OBL) technique, and the other is a mutation method. The OBL technique for the initial population improves the convergence rate and the accuracy of the final result, and the mutation method helps it to approach the global optimum and avoid the local one. Three benchmark spatial truss optimization problems are selected from the literature to examine the efficiency of IWSA in comparison to other well-established algorithms as well as its standard version, WSA. The results reveal the viability and competitiveness of the IWSA algorithm in the framework of design optimization with frequency constraints in comparison to its standard version and other structural optimization algorithms.