Modeling of global and local stability in optimization of truss-like structures using frame elements

An approach to take into account global and local stability in the design optimization of truss‐like structures is presented. It is based on the use of frame elements and a single global stability constraint. A detailed discussion on key aspects of the proposed approach is presented, together with numerical examples. The proposed approach ensures global stability and does not require the use of Euler formula, avoiding several difficulties encountered in truss optimization. Besides, the examples illustrate that global stability is an important aspect to be taken into account in most practical cases.