{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T15:19:26Z","timestamp":1783610366689,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,5,30]],"date-time":"2022-05-30T00:00:00Z","timestamp":1653868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Clean Sky 2, JTI-SAT, OPTICOMS Project","award":["699740"],"award-info":[{"award-number":["699740"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Structural health monitoring has multifold aims. Concerning composite structures, the main objectives are perhaps reducing costs by shifting from scheduled to on-demand maintenance and reducing weight by removing redundant precautions as the insertion of chicken fasteners to for ensuring joint safety in cases of bonding layer fail. Adhesion defects may be classified along different types, for instance distinguishing between glue deficiency or de-bonding. This paper deals with a preliminary numerical characterization of adhesive layer imperfections on a representative aircraft component. The multipart composite spar is made of two plates and two corresponding C-beams, bonded together to form an almost squared boxed section beam. A numerical test campaign was devoted to extract relevant information from different defect layouts and to try to assess some parameters that could describe their peculiarities. A focus was then given to macroscopic evidence of fault effects behavior, as localization, reciprocal interference, impact on structural response, and so on. A proprietary code was finally used to retrieve the presence and size of the imperfections, correlating numerical outcomes with estimations. Activities were performed along OPTICOMS, a European project funded within the Clean Sky 2 Joint Technology Initiative (JTI).<\/jats:p>","DOI":"10.3390\/s22114152","type":"journal-article","created":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T02:30:06Z","timestamp":1653964206000},"page":"4152","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["De-Bonding Numerical Characterization and Detection in Aeronautic Multi-Element Spars"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8150-147X","authenticated-orcid":false,"given":"Antonio","family":"Concilio","sequence":"first","affiliation":[{"name":"Adaptive Structures Division, the Italian Aerospace Research Centre (CIRA), 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Ciminello","sequence":"additional","affiliation":[{"name":"Adaptive Structures Division, the Italian Aerospace Research Centre (CIRA), 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernardino","family":"Galasso","sequence":"additional","affiliation":[{"name":"Adaptive Structures Division, the Italian Aerospace Research Centre (CIRA), 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6859-1922","authenticated-orcid":false,"given":"Lorenzo","family":"Pellone","sequence":"additional","affiliation":[{"name":"Adaptive Structures Division, the Italian Aerospace Research Centre (CIRA), 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Umberto","family":"Mercurio","sequence":"additional","affiliation":[{"name":"Adaptive Structures Division, the Italian Aerospace Research Centre (CIRA), 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gianvito","family":"Apuleo","sequence":"additional","affiliation":[{"name":"Research Division, Piaggio Aerospace Industries, 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aniello","family":"Cozzolino","sequence":"additional","affiliation":[{"name":"Research Division, Piaggio Aerospace Industries, 81043 Capua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iddo","family":"Kressel","sequence":"additional","affiliation":[{"name":"Advanced Structural Technologies, Engineering Center, Israel Aerospace Industries (IAI), Ben Gurion International Airport, Tel Aviv 70100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shay","family":"Shoham","sequence":"additional","affiliation":[{"name":"Advanced Structural Technologies, Engineering Center, Israel Aerospace Industries (IAI), Ben Gurion International Airport, Tel Aviv 70100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6406-3316","authenticated-orcid":false,"given":"David","family":"Bardenstein","sequence":"additional","affiliation":[{"name":"Advanced Structural Technologies, Engineering Center, Israel Aerospace Industries (IAI), Ben Gurion International Airport, Tel Aviv 70100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"322","DOI":"10.1016\/j.jsv.2015.06.028","article-title":"Design optimization of composite structures operating in acoustic environments","volume":"355","author":"Chronopoulos","year":"2015","journal-title":"J. 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