{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T08:51:31Z","timestamp":1773305491984,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,14]],"date-time":"2022-11-14T00:00:00Z","timestamp":1668384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Because the certification of aircraft structures requires significant costs and time-consuming experimental tests, all the studies carried out are strong contributions to the applicability of repairs based on adhesively bonded fibre composite patches. In this context, the main goal of this study aims to analyse the effect of the impact position on the multi-impact response of repaired composites. The results will be compared with those obtained in composites containing holes. Therefore, experimental tests will be carried out using an energy of 8 J and centrally supported samples. It was noted that the patch region proved to be very sensitive to impact due to its thickness. Full perforation occurred after two to three impacts, and to obtain higher strength it would be necessary to increase the thickness of the patch. However, depending on the location of the repair, this could bring aerodynamic problems. For the distance of 15 mm from the centre, an overlap region, the repaired laminate shows 494.7% higher impact strength than a laminate with a hole. In this case, the effect of the stress concentration is determinant in the impact fatigue life. Finally, for the 35 mm distances that are close to the border, no significant changes in impact fatigue life were observed for both the repaired laminates and those containing the hole. This leads to the conclusion that the border effect is much more significant than the presence of the hole for this distance.<\/jats:p>","DOI":"10.3390\/ma15228039","type":"journal-article","created":{"date-parts":[[2022,11,15]],"date-time":"2022-11-15T02:32:16Z","timestamp":1668479536000},"page":"8039","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Effect of Impact Position on Repaired Composite Laminates Subjected to Multi-Impacts"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5203-3670","authenticated-orcid":false,"given":"Paulo N. B.","family":"Reis","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, CEMMPRE, University of Coimbra, Rua Lu\u00eds Reis Santos, Pinhal de Marrocos, 3030-788 Coimbra, Portugal"}]},{"given":"Sara R. M.","family":"Coelho","sequence":"additional","affiliation":[{"name":"Department of Aerospace Sciences, University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]},{"given":"Abderrezak","family":"Bezazi","sequence":"additional","affiliation":[{"name":"Laboratoire de M\u00e9canique Appliqu\u00e9e des Nouveaux Mat\u00e9riaux (LMANM), Universit\u00e9 8 Mai 1945, Guelma 24000, Algeria"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"111427","DOI":"10.1016\/j.compstruct.2019.111427","article-title":"Fatigue behavior of concrete beams reinforced with glass and carbon-fiber reinforced polymer (GFRP\/CFRP) bars after exposure to elevated temperatures","volume":"229","author":"Zhao","year":"2019","journal-title":"Compos. Struct."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1371","DOI":"10.1016\/S1359-835X(98)00060-8","article-title":"Adhesively-bonded repairs to fibre-composite materials I: Experimental","volume":"29","author":"Charalambides","year":"1998","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/S0143-7496(01)00029-X","article-title":"Through-thickness shape optimisation of bonded repairs and lap-joints","volume":"22","author":"Kaye","year":"2002","journal-title":"Int. J. Adhes. Adhes."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1016\/S0263-8223(97)80011-6","article-title":"Design and analysis of test coupons for composite blade repairs","volume":"37","author":"Oztelcan","year":"1997","journal-title":"Compos. Struct."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1419","DOI":"10.1016\/j.compositesa.2008.12.011","article-title":"Micrographic studies on adhesively bonded scarf repairs to thick composite aircraft structure","volume":"40","author":"Whittingham","year":"2009","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1016\/j.compstruct.2010.08.021","article-title":"Tensile behaviour of patch-repaired CFRP laminates","volume":"93","author":"Cheng","year":"2011","journal-title":"Compos. Struct."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1016\/S0263-8223(99)00033-1","article-title":"Compressive behaviour of CFRP laminates repaired with adhesively bonded external patches","volume":"45","author":"Soutis","year":"1999","journal-title":"Compos. Struct."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1383","DOI":"10.1016\/S1359-835X(98)00061-X","article-title":"Adhesively-bonded repairs to fibre-composite materials II: Finite element modelling","volume":"29","author":"Charalambides","year":"1998","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1948","DOI":"10.1016\/j.compscitech.2005.04.007","article-title":"Modelling single and double-lap repairs on composite materials","volume":"65","author":"Campilho","year":"2005","journal-title":"Compos. Sci. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.tafmec.2005.01.004","article-title":"Progressive damage modelling of bonded composite repairs","volume":"43","author":"Papanikos","year":"2005","journal-title":"Theor. Appl. Fract. Mech."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1103","DOI":"10.1016\/S0266-3538(00)00011-7","article-title":"Strength prediction of patch-repaired CFRP laminates loaded in compression","volume":"60","author":"Hu","year":"2000","journal-title":"Compos. Sci. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1016\/j.compstruct.2006.08.024","article-title":"Progressive failure analysis of bonded composite repairs","volume":"81","author":"Liu","year":"2007","journal-title":"Compos. Struct."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1177\/1099636203005002108","article-title":"The static mechanical performance of repaired composite sandwich beams: Part I\u2014Experimental characterisation","volume":"5","author":"Smahdi","year":"2003","journal-title":"J. Sandw. Struct. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.msea.2016.11.030","article-title":"Experimental investigation of single and repeated impacts for repaired honeycomb sandwich structures","volume":"682","author":"Bora","year":"2017","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1016\/j.compstruct.2015.08.022","article-title":"Compression after impact strength of repaired GFRP composite laminates under repeated impact loading","volume":"133","author":"Andrew","year":"2015","journal-title":"Compos. Struct."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3014","DOI":"10.1002\/pc.25593","article-title":"Impact response of repaired sandwich structures","volume":"41","author":"Barbero","year":"2020","journal-title":"Polym. Compos."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1016\/j.compstruct.2017.02.069","article-title":"Effects of external patch configuration on repaired composite laminates subjected to multi-impacts","volume":"168","author":"Coelho","year":"2017","journal-title":"Compos. Struct."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3005","DOI":"10.1016\/j.matpr.2020.09.323","article-title":"Influence of the impact position on scarf repair composite under low velocity impact: FEA investigation","volume":"38","author":"Kumari","year":"2021","journal-title":"Mater. Today Proc."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1016\/j.compositesb.2018.12.153","article-title":"Low-velocity impact behaviors of repaired CFRP laminates: Effect of impact location and external patch configurations","volume":"163","author":"Hou","year":"2019","journal-title":"Compos. Part B Eng."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/S0263-8223(03)00032-1","article-title":"Experimental investigations on the response of stitched\/unstitched woven S2-glass\/SC15 epoxy composites under single and repeated low velocity impact loading","volume":"61","author":"Hosur","year":"2003","journal-title":"Compos. Struct."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/S0143-7496(98)90028-8","article-title":"Development of a generic repair joint for certification of bonded composite repairs","volume":"19","author":"Chalkley","year":"1999","journal-title":"Int. J. Adhes. Adhes."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1080\/00218464.2014.883315","article-title":"On the certification of bonded repairs to primary composite aircraft components","volume":"91","author":"Baker","year":"2015","journal-title":"J. Adhes."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1080\/13588265.2019.1702412","article-title":"Effect of fibre orientation on damage resistance of composite laminates","volume":"26","author":"Khan","year":"2021","journal-title":"Int. J. Crashworth."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"E220","DOI":"10.1111\/j.1475-1305.2008.00534.x","article-title":"The Influence of the boundary conditions on low-velocity impact composite damage","volume":"47","author":"Amaro","year":"2011","journal-title":"Strain"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3520","DOI":"10.1016\/j.compstruct.2012.05.025","article-title":"Impact response of kevlar composites with filled epoxy matrix","volume":"94","author":"Reis","year":"2012","journal-title":"Compos. Struct."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.compositesb.2012.10.028","article-title":"Impact response of kevlar composites with nanoclay enhanced epoxy matrix","volume":"46","author":"Reis","year":"2013","journal-title":"Compos. Part B Eng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/S0734-743X(01)00040-9","article-title":"Low velocity impact tests of laminate glass-fiber-epoxy matrix composite material plates","volume":"27","author":"Belingardi","year":"2002","journal-title":"Int. J. Impact Eng."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/S0263-8223(02)00185-X","article-title":"The response of laminated composite plates under low-velocity impact loading","volume":"59","author":"Aslan","year":"2003","journal-title":"Compos. Struct."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/j.compstruct.2004.07.024","article-title":"Studies on the low-velocity impact response of woven hybrid composites","volume":"67","author":"Hosur","year":"2005","journal-title":"Compos. Struct."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"898","DOI":"10.1177\/0731684413478993","article-title":"Impact response of sandwich composites with nano-enhanced epoxy resin","volume":"32","author":"Reis","year":"2013","journal-title":"J. Reinf. Plast. Compos."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"903","DOI":"10.1016\/S1359-835X(00)00061-0","article-title":"Delamination threshold loads for low velocity impact on composite laminates","volume":"31","author":"Schoeppner","year":"2000","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/j.compositesb.2004.04.003","article-title":"Damage in CFRPs due to low velocity impact at low temperature","volume":"36","author":"Zaer","year":"2005","journal-title":"Compos. Part B Eng."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1515\/polyeng-2011-0101","article-title":"Influence of the specimen thickness on low velocity impact behavior of composites","volume":"32","author":"Amaro","year":"2012","journal-title":"J. Polym. Eng."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1016\/j.polymdegradstab.2012.12.029","article-title":"Effects of alkaline and acid solutions on glass\/epoxy composites","volume":"98","author":"Amaro","year":"2013","journal-title":"Polym. Degrad. Stab."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/j.compstruct.2007.04.015","article-title":"An experimental study of damage accumulation in balanced CFRP laminates due to repeated impact","volume":"83","author":"Nash","year":"2008","journal-title":"Compos. Struct."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1177\/002199837400800303","article-title":"Stress Fracture Criteria for Laminated Composites Containing Stress Concentrations","volume":"8","author":"Whitney","year":"1974","journal-title":"J. Compos. Mater."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Reis, P.N.B., Coelho, C.A.C.P., and Navalho, F.V.P. (2021). Impact response of composite sandwich cylindrical shells. Appl. Sci., 11.","DOI":"10.3390\/app112210958"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.compositesb.2016.05.021","article-title":"Experimental study of temperature effects on composite laminates subjected to multi-impacts","volume":"98","author":"Amaro","year":"2016","journal-title":"Compos. Part B Eng."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"115788","DOI":"10.1016\/j.compstruct.2022.115788","article-title":"Multi-impact behaviour of composite laminates under constant and different energy levels","volume":"294","author":"Reis","year":"2022","journal-title":"Compos. Struct."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1111\/j.1475-1305.2008.00520.x","article-title":"Delamination effect on bending behaviour in carbon\u2013epoxy composites","volume":"47","author":"Amaro","year":"2011","journal-title":"Strain"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1147","DOI":"10.1016\/1359-835X(96)00083-8","article-title":"Impact damage and residual strengths of woven fabric glass\/polyester laminates","volume":"27","author":"Davies","year":"1996","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1123","DOI":"10.1016\/1359-835X(96)00074-7","article-title":"Review of low-velocity impact properties of composite materials","volume":"27","author":"Richardson","year":"1996","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"4573","DOI":"10.1002\/pc.25325","article-title":"Intra-laminar toughening mechanisms to enhance impact damage tolerance of 2D woven composite laminates via yarn-level fiber hybridization and fiber architecture","volume":"40","author":"Dalfi","year":"2019","journal-title":"Polym. Compos."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/15\/22\/8039\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:17:52Z","timestamp":1760145472000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/15\/22\/8039"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,14]]},"references-count":43,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["ma15228039"],"URL":"https:\/\/doi.org\/10.3390\/ma15228039","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,11,14]]}}}