PSI - Issue 37

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ScienceDirect

Procedia Structural Integrity 37 (2022) 698–705 Structural Integrity Procedia 00 (2022) 000–000 Structural Integrity Procedia 00 (2022) 000–000

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© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira © 2022 The Authors. Published by Elsevier B.V. his is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of Pedro Mig el Guimaraes Pir s Moreira. Keywords: damage localization; finite di ff erences; laminated composite materials; finite element method; modal analysis Abstract Laminated composite materials are a staple of modern material development, with extremely strong fibers being combined with resins to form versatile and e ffi cient engineering structures. However, the advancements in material development must be accom panied by equally advanced methods for damage detection, as these materials develop inherently unique failure modes. This thesis aims to further the study of the use of modal shapes and their spatial derivatives to damage localization in laminated composite rectangular plates. ANSYS ® Parametric Design Language ( PDL) is used to perform Finite Element simulations of plates with several damage scenarios and damage mechanics models. MATLAB ® is used to postprocess these simulations results, namely by calculating the derivatives using the Finite Di ff erence Method, applying three di ff erent Damage Detection Methods, including one that is being proposed here. To mimic experimental conditions and testing the resilience of the derivative orders, di ff erent noise levels are introduced in the results of the Finite Element simulations. A Quality Index is employed to quantitatively evaluate the solutions, mainly regarding the response to the introduced noise. The results show that the di ff erent Damage Detection Methods tested have comparable results in terms of quality. These results also show that the damage detectability is higher when the dam aged areas coincide with high displacement / curvature areas of the mode shapes and that higher noise levels have a more noticeable negative impact when employing higher-order derivatives. © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira. Keywords: damage localization; finite di ff erences; laminated composite materials; finite element method; modal analysis ICSI 2021 The 4th International Conference on Structural Integrity On the use of finite di ff erences for vibration-based damage localization in laminated composite plates T. Oliveira a , J.V. Arau´ jo dos Santos b, ∗ , H. Lopes c a Instituto Superior Te´cnico, Universidade de Lisboa, Lisboa, Portugal b IDMEC, Instituto Superior Te´cnico, Universidade de Lisboa, Lisboa, Portugal c DEM-ISEP, Instituto Polite´cnico do Porto, Porto, Portugal Abstract Laminated composite materials are a staple of modern material development, with extremely strong fibers being combined with resins to form versatile and e ffi cient engineering structures. However, the advancements in material development must be accom panied by equally advanced methods for damage detection, as these materials develop inherently unique failure modes. This thesis aims to further the study of the use of modal shapes and their spatial derivatives to damage localization in laminated composite rectangular plates. ANSYS ® Parametric Design Language (APDL) is used to perform Finite Element simulations of plates with several damage scenarios and damage mechanics models. MATLAB ® is used to postprocess these simulations results, namely by calculating the derivatives using the Finite Di ff erence Method, applying three di ff erent Damage Detection Methods, including one that is being proposed here. To mimic experimental conditions and testing the resilience of the derivative orders, di ff erent noise levels are introduced in the results of the Finite Element simulations. A Quality Index is employed to quantitatively evaluate the solutions, mainly regarding the response to the introduced noise. The results show that the di ff erent Damage Detection Methods tested have comparable results in terms of quality. These results also show that the damage detectability is higher when the dam aged areas coincide with high displacement / curvature areas of the mode shapes and that higher noise levels have a more noticeable negative impact when employing higher-order derivatives. ICSI 2021 The 4th International Conference on Structural Integrity On the use of finite di ff erences for vibration-based damage localization in laminated composite plates T. Oliveira a , J.V. Arau´ jo dos Santos b, ∗ , H. Lopes c a Instituto Superior Te´cnico, Universidade de Lisboa, Lisboa, Portugal b IDMEC, Instituto Superior Te´cnico, Universidade de Lisboa, Lisboa, Portugal c DEM-ISEP, Instituto Polite´cnico do Porto, Porto, Portugal

∗ Corresponding author. Tel.: + 0-351-21-841-9463 ; fax: + 0-351-21-841-7915. E-mail address: viriato@tecnico.ulisboa.pt ∗ Corresponding author. Tel.: + 0-351-21-841-9463 ; fax: + 0-351-21-841-7915. E-mail address: viriato@tecnico.ulisboa.pt

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira 10.1016/j.prostr.2022.01.140 2210-7843 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira. 2210-7843 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira.