{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T20:02:01Z","timestamp":1773518521257,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,11,29]],"date-time":"2024-11-29T00:00:00Z","timestamp":1732838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Sciences and Engineering Research Council of Canada (NSERC)"},{"name":"Fonds de recherche du Qu\u00e9bec\u2014Nature et technologie (FRQNT)"},{"name":"Deanship of Research and Graduate Studies (DRG) at Ajman University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This paper presents the results of an experimental study involving 20 tests performed on elliptical concrete columns confined with externally bonded carbon fiber-reinforced polymer (EB-CFRP) laminates. The study aimed to evaluate the effects of elliptical aspect ratio (A\/B) as well as confinement rigidity (number of EB-FRP layers) on confinement effectiveness. The experimental program consisted of one series of control concrete columns (unstrengthened) and three additional series, each one strengthened with one, two and three layers of EB-CFRP sheets, respectively. Furthermore, each series considered five elliptical aspect ratios (A\/B) ranging from 1.0 to 1.6. Following compressive concentric tests until failure, the results were analyzed to characterize the confinement level with an increasing number of EB-CFRP layers as a function of the elliptical aspect ratio. The results show considerable enhancements in compressive strength and in the ductility of the confined columns. Furthermore, this improvement is amplified as the number of EB-CFRP layers increases, indicating a proportional relationship between the compressive strength and the number of CFRP layers. It is found that the ultimate strength of EB-CFRP-confined columns with three layers reached up to 130% compared to the control specimens. However, increasing the elliptical aspect ratio reduced the compressive strength and ductility of confined columns. This study investigated the relation between the CFRP hoop and axial strains and the elliptical aspect ratios. Moreover, through comparison, the results reveal that the prediction models proposed by the Canadian standards S806-12 and S6-19 do not capture the negative effect of the elliptical aspect ratio in confined concrete columns.<\/jats:p>","DOI":"10.3390\/sym16121595","type":"journal-article","created":{"date-parts":[[2024,11,29]],"date-time":"2024-11-29T05:02:22Z","timestamp":1732856542000},"page":"1595","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Experimental Investigation on the Effectiveness of EB-CFRP Confinement of Elliptical Concrete Columns"],"prefix":"10.3390","volume":"16","author":[{"given":"Zine El Abidine","family":"Benzeguir","sequence":"first","affiliation":[{"name":"Department of Construction Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), Universit\u00e9 du Qu\u00e9bec, Montreal, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1672-548X","authenticated-orcid":false,"given":"Omar","family":"Chaallal","sequence":"additional","affiliation":[{"name":"Department of Construction Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), Universit\u00e9 du Qu\u00e9bec, Montreal, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7349-6367","authenticated-orcid":false,"given":"Ahmed","family":"Godat","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, College of Engineering and Information Technology, Ajman University, Ajman P.O. Box 346, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0184-6732","authenticated-orcid":false,"given":"Rami A.","family":"Hawileh","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, College of Engineering, American University of Sharjah, Sharjah P.O. Box 26666, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.tws.2016.10.013","article-title":"Behaviour of concrete-filled cold-formed elliptical hollow sections with varying aspect ratios","volume":"110","author":"Liu","year":"2017","journal-title":"Thin-Walled Struct."},{"key":"ref_2","first-page":"500","article-title":"Behavior of concrete columns confined with fiber reinforced polymer tubes","volume":"96","author":"Mohamed","year":"1999","journal-title":"Mater. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"396","DOI":"10.1016\/j.conbuildmat.2010.06.013","article-title":"Concrete column shape modification with FRP shells and expansive cement concrete","volume":"25","author":"Yan","year":"2010","journal-title":"Constr. Build. 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ASTM C39\/39-18 (Standard No. ASTM-C39\/39-18)."}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/16\/12\/1595\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:42:32Z","timestamp":1760114552000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/16\/12\/1595"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,11,29]]},"references-count":37,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["sym16121595"],"URL":"https:\/\/doi.org\/10.3390\/sym16121595","relation":{},"ISSN":["2073-8994"],"issn-type":[{"value":"2073-8994","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,11,29]]}}}