Issue 77

L. Marsavina et alii, Fracture and Structural Integrity, 77 (2026) 107-119; DOI: 10.3221/IGF-ESIS.77.08

Compression tests The compression tests of lattice structures were performed with 5 mm/min displacement control, at room temperature (23 °C) using a Zwick ProLine Z005 testing machine. A digital camera was used to record the test and analyse the deformation behaviour of the lattice structures. Typical load-displacement curves for one specimen are shown in Fig. 2 for the three lattice structure considered. The E.a. inspired lattice structure exhibits the maximum value of compressive force, followed by the triangle honeycomb and, finally, by the square lattice. The resulted failures of the lattice structures under compression are different (Fig. 3). The square lattice exhibits an elastic buckling followed by the faces bend and tensile before fracture (Fig. 3a). For the triangle lattice, a local buckling occurs at the edge of the structure and then the struts of the structure failed due to a combination of tensile and bending (Fig. 3b). The E.a. inspired structure mitigated pronounced buckling or local buckling phenomena. The fracture occurred at 45° through the structure by shear. The measurements of the specimen’s mass and dimensions, and maximum load are presented in Tab. 2.

(a) (c) Figure 3: Failures frame for a) square-lattice; b) triangular-lattice; c) E.a. inspired structure. (b)

Specimen dimensions (L 1 xL 2 xt)

Density  lattice  [g/cm 3 ]

Specimen Number.

Weight, m [g] 13.447 12.902 13.263 13.257 20.865 20.864 20.505 20.767

Maximum load F max [N]

L 1 [mm]

L 2 [mm]

t [mm]

Square-lattice

P1 P2 P3 P4 T1 T2 T3 T4 C1 C2 C3 C4

59.80 59.70 59.75 59.75 59.80 59.80 59.75 59.80 59.70 59.75 59.75 59.80

59.80 59.75 59.70 59.70 59.80 59.80 59.80 59.80 59.75 59.70 59.73 59.80

15.10 15.05 15.05 15.00 15.15 15.05 15.05 15.05 15.15 15.16 15.15 15.17

0.249 0.240 0.247 0.248 0.385 0.388 0.381 0.386 0.476 0.475 0.493 0.479

801 844

1050 1060

Triangular-lattice

2720 2980 3090 3130 4990 4760 5060 4740

Euplectella Aspergillum inspired

25.701 25.708

26.68

25.996

Table 2: Specimens dimensions and maximum load.

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