PSI - Issue 80

Pavel Šandera et al. / Procedia Structural Integrity 80 (2026) 169–176 Šandera / Structural Integrity Procedia 00 (2025) 000 – 000

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Fig. 1. The dependences of the roughness parameter S dr on the plastic zone size R pz for both porosities.

Fig. 2. The statistical frequency distributions of S dr -values related to variants of the constructed fracture surface for both porosities.

The previous measurements on several scaffold filaments fractured under the cyclic compression using the confocal laser scanning microscopy (CLSM) led to mean values S dr p = 2.2 ± 0.4 for porous fib ers and S dr c = 1.2 ± 0.3 for compact fibers as reported by Slámečka et al. (2023) . These measured values correspond well to those computed for R pz ϵ (50, 80) µm (see Fig. 1), which indicates a reasonable prediction ability of the model. We believe that this will be confirmed by the results of a currently starting CLSM roughness analysis of fibers fractured in the cyclic three point bend tests, where the loading conditions and the plastic zone sizes are much better defined than those in the individual scaffold filaments fractured under cyclic compression. Note that the critical sites of scaffold fibers where fracture occurs during the cyclic compression are subjected to a local cyclic bending loading as follows from the model published by Skalka et al. (2019).