PSI - Issue 81

Andrejs Kovalovs et al. / Procedia Structural Integrity 81 (2026) 388–395

395

uncertainty of approximately ±0.5% for E 1 and G 12 and about ±1% for E 2 . This level of precision demonstrates the high numerical stability of the proposed approach. Thus, compared with direct FE-based optimization, the RSM achieves sufficient reduction in computation time while maintaining the same level of accuracy. Furthermore, since all analyses were conducted within a virtual experiment framework, the obtained results confirm that the methodology is reliable and ready for transition to physical testing with real modal data. 4. Conclusions The RSM-based virtual experiment was conducted to verify the accuracy and robustness of the proposed vibration-based identification methodology for laminated CFRP plates. The main conclusions are as follows: 1. The virtual experiment demonstrated that the inverse identification reproduces the reference elastic constants of both unidirectional and twill-weave laminates with deviations below 1% for the principal in-plane moduli E 1 and G 12 . Modal frequencies agreed with the reference FE data within 0.1%. 2. The method reliably captured material anisotropy, distinguishing strongly anisotropic unidirectional laminates ( E 1 / E 2 = 16) from quasi-isotropic twill-weave laminates ( E 1 = E 2 ). 3. Noticeable discrepancies exceeding 5% were observed for the out-of-plane shear modulus G 23 in the unidirectional laminate and for E 3 , ν 13 , and ν 23 in the twill-weave laminate. These deviations are attributed to the low sensitivity of the considered vibration modes to through-thickness deformation and the thin-plate assumption adopted in the model. 4. The response-surface methodology provided high computational efficiency – sufficient reducing the identification time compared with direct FE optimization – while maintaining accuracy and numerical stability. 5. The results of the virtual experiment confirm that the developed procedure is a reliable and efficient tool for determining selected elastic constants of anisotropic composite laminates and is ready for transition to laboratory validation using real modal data. Overall, the proposed virtual-experiment-based identification procedure provides an efficient methodological framework for the non-destructive characterization of advanced composite structures. Acknowledgements The authors gratefully acknowledge the support of the Ukrainian- Latvian bilateral scientific project “Development of a methodology for health monitoring and diagnosis of local damage in composite structural elements using smart materials”, f unded by the Ministries of Education and Science of Ukraine and Latvia (2025-2026). References Akishin, P.Y., Barkanov, E.N., Wesolowski, M., Kolosova, E.M., 2014. Static and dynamic techniques for non-destructive elastic material properties characterisation. Proceedings of APM 2014, 164 – 175. Acosta- Flores, M., Eraña - Díaz, M.L., 2024. Experimental determination of elastic properties in laminate composite material orthotropic plies. Journal of Mechanical Science and Technology 38, 1317 – 1328. https://doi.org/10.1007/s12206-024-0226-6 Barkanov, E., Skukis, E., Petitjean, B., 2009. Characterisation of viscoelastic layers in sandwich panels via an inverse technique. Journal of Sound and Vibration 327, 402 – 412. https://doi.org/10.1016/j.jsv.2009.07.011 Huang, C., Chen, Y., 2025. Nondestructive identification of elastic constants of composites via inversion of measured modal data. Proc. SPIE Smart Structures and Materials 13437, 134371U. https://doi.org/10.1117/12.3051151 Kovalovs, A., Chate, A., Kulakov, V., Mironov, A., et al., 2024. The effect of manufacture process on material properties of laminated composite cylinders using non-destructive technique. MATEC Web of Conferences 396, 02001. https://doi.org/10.1051/matecconf/202439602001 Kovalovs, A., Kuzmickis, V., Kulakov, V., 2025. Determining the properties of a layered composite plate made of twill-weave glass fibre fabric using non destructive testing methods. Journal of Composite Science 9, 546. https://doi.org/10.3390/jcs9100546 Li, N., Ben Tahar, M., Aboura, Z., Khellil, K., 2018. A vibration-based identification of elastic properties of stitched sandwich panels. Journal of Composite Materials 53(5), 579 – 590. https://doi.org/10.1177/0021998318788141 Liu, C.W., Kam, T.Y., 2025. Identification of material constants for composite materials using a sensitivity-based multi-level optimization method. Materials 18(12), 2737. https://doi.org/10.3390/ma18122737 Matter, M., Gmur, T., Cugnoni, J., Schorderet, A., 2009. Numerical-experimental identification of the elastic and damping properties in composite plates. Composite Structures 90, 180 – 187. https://doi.org/10.1016/j.compstruct.2009.03.001 Niutta, C.B., Spadoni, A., Collet, M., 2021. Nondestructive determination of local material properties of composites using vibroacoustic signatures. Composite Structures 268, 113960. https://doi.org/10.1016/j.compstruct.2021.113607 Rikards, R., 2003. Identification of mechanical properties of laminates. Mechanics of Advanced Materials and Structures 10, 335 – 352. https://doi.org/10.1007/978 3-7091-2544-1_4 Rikards, R., Auzins, J., 2004. Response surface method for solution of structural identification problems. Inverse Problems in Science and Engineering 12, 59 – 70. https://doi.org/10.1080/10682760310001597446 Wollmann, T., Modler, N., Dannemann, M., Langkamp, A., Nitschke, S., Filippatos, A., 2016. Design and testing of composite compressor blades with focus on the vibration behaviour. Composites: Part A 90, 278 – 288. https://doi.org/10.1016/j.compositesa.2016.06.012