A new evolutionary topology optimization method for truss structures towards practical design applications

This paper presents a new topology optimization method and a comprehensive workflow for the practical design of truss structures. It begins with discussing practical design requirements for truss topology optimization and then introduces a technique for creating arbitrarily shaped ground structures suitable for complex geometries. To address limitations in current truss optimization methods, we propose a dual-material truss-bidirectional evolutionary structural optimization (DMT-BESO) method. This approach utilizes two materials that differ significantly in tensile and compressive allowable stresses and moduli of elasticity . The DMT-BESO method integrates the minimum energy principle with the full-stress design criterion, using bar cross-sectional areas as design variables to achieve simultaneous topology and size optimization. By considering stress constraints, this method ensures compliance with industry standards, enhancing both safety and material utilization. Additionally, a structural complexity control strategy is proposed to generate a near-optimal truss design and simplify the optimized design while maintaining efficiency, making it more suitable for practical applications. The effectiveness of the DMT-BESO method and its complexity control strategy is validated through numerical examples and the design of an arch bridge of composite materials.