Optimal Design of Wire-and-Arc Additively Manufactured I-Beams for Prescribed Deflection

  • Matteo Bruggi Politecnico di Milano
  • Vittoria Laghi University of Bologna
  • Tomaso Trombetti University of Bologna


Alloys fabricated by wire-and-arc additive manufacturing (WAAM) exhibit a peculiar anisotropy in their elastic response. As shown by recent numerical investigations concerning the optimal design of WAAM-produced structural components, the printing direction remarkably affects the stiffness of the optimal layouts, as well as their shape. So far, single-plate specimens have been investigated. In this contribution, the optimal design of WAAM-produced I-beams is addressed assuming that a web plate and two flat flanges are printed and subsequently welded to assemble the structural component. A formulation of displacement-constrained topology optimization is implemented to design minimum weight specimens resorting to a simplified two-dimensional model of the I-beam. Comparisons are provided addressing solutions achieved by performing topology optimization with (i) conventional isotropic stainless steel and with (ii) WAAM-produced orthotropic stainless steel at prescribed printing orientations. Lightweight solutions arise whose specific shape depends on the selected material and the adopted printing direction.


structural optimization, topology optimization, wire-and-arc additive manufacturing, I-beams, orthotropic material, additive manufacturing, 3D printing,


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Jul 1, 2022
How to Cite
BRUGGI, Matteo; LAGHI, Vittoria; TROMBETTI, Tomaso. Optimal Design of Wire-and-Arc Additively Manufactured I-Beams for Prescribed Deflection. Computer Assisted Methods in Engineering and Science, [S.l.], july 2022. ISSN 2299-3649. Available at: <https://cames.ippt.pan.pl/index.php/cames/article/view/469>. Date accessed: 10 aug. 2022. doi: http://dx.doi.org/10.24423/cames.469.
[CLOSED] Engineering Optimization