Issue 78

M. Habashneh et alii, Fracture and Structural Integrity, 78 (2026) 409-431; DOI: 10.3221/IGF-ESIS.78.24

Influence of mesh size, evolutionary rate, and filter radius on geometrically nonlinear topology optimization

Muayad Habashneh, Majid Movahedi Rad Department of Structural and Geotechnical Engineering, Széchenyi István University, Gy ő r, Hungary habashneh.muayad@sze.hu, hhttps://orcid.org/0000-0002-2328-2990 majidmr@sze.hu, https://orcid.org/0000-0002-8393-724X

Citation: Habashneh, M., Rad, M. M., Influence of mesh size, evolutionary rate, and filter radius on geometrically nonlinear topology optimization, Fracture and Structural Integrity, 78 (2026) 409-431.

A BSTRACT . The BESO method is widely used to find efficient structural layouts through iterative material removal and addition. The method works well under linear conditions but things get more complicated when geometric nonlinearity is involved. Large displacements affect how the structure reaches equilibrium and this directly changes the sensitivity field and material update process making parameter selection much more critical. This paper studies three parameters systematically: mesh size, evolutionary rate and filter radius. Three benchmark structures are tested including an L-shaped beam, a pinned rectangular plate and a U-shaped plate. Each parameter is changed one at a time while the others stay fixed. Nodal displacement at the load point is used alongside topology results as a direct stiffness measure. Results show that the main load path stays intact across all tested cases but secondary bracing members are noticeably affected by coarser meshes, higher evolutionary rates and larger filter radii. The filter radius had the strongest overall influence on both topology and stiffness. The findings provide practical guidance for parameter selection and highlight the need to critically reassess algorithmic settings developed for linear BESO before applying them in large displacement structural optimization. K EYWORDS . Topology optimization, BESO, Geometric nonlinearity, Large displacement analysis, Mesh sensitivity, Parametric study.

Received: 25.06.2026 Accepted: 14.09.2026 Published: 16.09.2026 Issue: 10.2026

Copyright: © 2026 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

I NTRODUCTION tructural topology optimization has grown into one of the most useful computational tools available for structural design. Rather than simply adjusting the sizes or shapes of predefined members it allows material to be freely distributed across a design domain which often leads to load-carrying layouts that would never emerge from conventional approaches [2,6,14,17]. Among the many methods developed for this purpose the Bi-Directional Evolutionary S

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