{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T05:27:19Z","timestamp":1771651639379,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,15]],"date-time":"2021-09-15T00:00:00Z","timestamp":1631664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["11772115 and U1765204"],"award-info":[{"award-number":["11772115 and U1765204"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"publisher","award":["2019B52914"],"award-info":[{"award-number":["2019B52914"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["BK20171439"],"award-info":[{"award-number":["BK20171439"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Identification of cracks in beam-type components is significant to ensure the safety of structures. Among the approaches relying on mode shapes, the concept of transverse pseudo-force (TPF) has been well proved for single and multiple crack identification in beams made of isotropic materials; however, there is a noticeable gap between the concept of TPF and its applications in composite laminated beams. To fill this gap, an enhanced TPF approach that relies on perturbation to dynamic equilibrium is proposed for the identification of multiple cracks in composite laminated beams. Starting from the transverse equation of motion, this study formulates the TPF in a composite laminated beam for the identification of multiple cracks. The capability of the approach is numerically verified using the FE method. The applicability of the approach is experimentally validated on a carbon fiber-reinforced polymer laminated beam with three cracks, the mode shapes of which are acquired through non-contact vibration measurement using a scanning laser vibrometer. In particular, a statistic manner is utilized to enable the approach to be feasible to real scenarios in the absence of material and structural information; besides, an integrating scheme is utilized to enable the approach to be capable of identifying cracks even in the vicinity of nodes of mode shapes.<\/jats:p>","DOI":"10.3390\/s21186171","type":"journal-article","created":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T23:34:11Z","timestamp":1631662451000},"page":"6171","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Identification of Multiple Cracks in Composite Laminated Beams Using Perturbation to Dynamic Equilibrium"],"prefix":"10.3390","volume":"21","author":[{"given":"Aimin","family":"Deng","sequence":"first","affiliation":[{"name":"Department of Engineering Mechanics, Hohai University, Nanjing 210098, China"},{"name":"Jiangsu Province Wind Power Structural Engineering Research Center, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maosen","family":"Cao","sequence":"additional","affiliation":[{"name":"Department of Engineering Mechanics, Hohai University, Nanjing 210098, China"},{"name":"Jiangsu Province Wind Power Structural Engineering Research Center, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qitian","family":"Lu","sequence":"additional","affiliation":[{"name":"Department of Engineering Mechanics, Hohai University, Nanjing 210098, China"},{"name":"Jiangsu Province Wind Power Structural Engineering Research Center, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3268-3646","authenticated-orcid":false,"given":"Wei","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Engineering Mechanics, Hohai University, Nanjing 210098, China"},{"name":"Jiangsu Province Wind Power Structural Engineering Research Center, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"115734","DOI":"10.1016\/j.jsv.2020.115734","article-title":"Nonlinear pseudo-force in a breathing crack to generate harmonics","volume":"492","author":"Xu","year":"2021","journal-title":"J. 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