Every week, we select a recently published Open Access article to feature. This week’s article is from the International Journal for Numerical Methods in Engineering and considers the topology optimization of hyperelastic structures.

The article’s abstract is given below, with the full article available to read here.

Granlund, G, Wallin, M, Tortorelli, D, Watts, S. Stress-constrained topology optimization of structures subjected to nonproportional loading. Int J Numer Methods Eng. 2023; 1– 19. doi: 10.1002/nme.7230

This work considers the topology optimization of hyperelastic structures for maximum stiffness (minimum compliance) subject to constraints on their volume and maximum stress. In contrast to almost all previous works, we subject the structures to nonproportional loading, wherein the maximum stress does not necessarily occur at the final load step. As such, the stress is constrained at each load step. The augmented Lagrangian method is used to formulate the optimization problem with its many constraints. In numerical examples, we investigate different load trajectories for the same terminal load and compare the optimized designs and their performances. The results show the importance of considering the entire load trajectory as the load history significantly influences the optimized designs.