{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T17:54:13Z","timestamp":1789494853427,"version":"build-2803163510"},"reference-count":68,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,11]],"date-time":"2020-11-11T00:00:00Z","timestamp":1605052800000},"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>This paper presents experimental, theoretical and numerical studies of wood-CFRP beams bonded with polyurethane (PUR) adhesive. The analyses include two types of CFRP (carbon fibre-reinforced polymer) strengthening configurations and pure glue laminated timber beams as a reference. Through detailed analyses of a double-lap connection on blocks with and without CFRP strips, the authors state that neglecting the cohesive stiffness of adhesive layers may lead to an overestimation of an overall beam\u2019s stiffness. This is significant with wood\u2013CFRP connections, which showed values two times lower than with wood\u2013wood connections. Theoretical modelling of the equivalent area used in a theory of composites provided much stiffer behaviour of the beams than in laboratory experiments. It proves that a PUR glue eliminates the possibility of using simple models that assume a perfect connection between bonded parts. These conclusions led the authors to use the finite element method (FEM) to take into account the cohesive stiffness. The FEM, based on the properties obtained from a double-lap joint analysis, allowed for the precise prediction of the elastic stiffness of the beams.<\/jats:p>","DOI":"10.3390\/ma13225075","type":"journal-article","created":{"date-parts":[[2020,11,11]],"date-time":"2020-11-11T19:08:28Z","timestamp":1605121708000},"page":"5075","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["The Effect of Glue Cohesive Stiffness on the Elastic Performance of Bent Wood\u2013CFRP Beams"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8134-5956","authenticated-orcid":false,"given":"Bartosz","family":"Kawecki","sequence":"first","affiliation":[{"name":"Faculty of Civil Engineering and Architecture, Lublin University of Technology, ul. Nadbystrzycka 40, 20-618 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4745-7705","authenticated-orcid":false,"given":"Jerzy","family":"Podg\u00f3rski","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering and Architecture, Lublin University of Technology, ul. Nadbystrzycka 40, 20-618 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1007\/s001070050486","article-title":"A shear test for structural adhesives used in the consolidation of old timber","volume":"59","author":"Lavisci","year":"2001","journal-title":"Holz als Roh- und Werkst."},{"key":"ref_2","first-page":"36","article-title":"Finite element analysis of wood adhesive joints","volume":"89","author":"Gereke","year":"2015","journal-title":"Ann. Warsaw Univ. 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