{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T09:05:01Z","timestamp":1790327101109,"version":"4.1.0"},"reference-count":28,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T00:00:00Z","timestamp":1790294400000},"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":["52471301"],"award-info":[{"award-number":["52471301"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52471301"],"award-info":[{"award-number":["52471301"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Compression testing of ultra-thick carbon-fibre-reinforced polymer (CFRP) laminates requires high loads to be transferred over a limited gripping length, while the stiffness discontinuity at the end-tab termination can initiate unintended local failure. This study examines the effects of taper geometry and tab thickness through combined-loading compression tests on four end-tab configurations, surface-strain measurements, fractography, and three-dimensional finite-element analysis. Multiple intralaminar failure indices were evaluated, and a Ye-type index was used to assess interlaminar initiation risk at the free edge. For the 20 mm thick tabs, introducing a 25 mm taper increased the mean compressive strength by 9.76%. At comparable nominal stresses near 330 MPa, the representative abrupt-ended specimen exhibited approximately twice the strain ranges in the shear and through-thickness directions of the representative tapered specimen. The numerical results showed that the tab-end stiffness gradient governed interlaminar load transfer: increasing taper length reduced the axial-stress gradient and the local interlaminar shear and through-thickness stress concentrations, with the calculated peak S13 decreasing from 48.01 to 18.36 MPa, while shifting the governing Hashin initiation mode from matrix compression to fibre compression. The measured strain localization and the observed fibre compression\u2013shear fracture, matrix shear cracking, and delamination were qualitatively consistent with the numerically identified three-dimensional stress concentrations. These results demonstrate that end-tab transition geometry governs local failure initiation and the measured load-carrying capacity of ultra-thick CFRP compression specimens.<\/jats:p>","DOI":"10.3390\/polym18192342","type":"journal-article","created":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T08:09:02Z","timestamp":1790323742000},"page":"2342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Experimental and Numerical Investigation of End-Tab Geometry Effects on the Compressive Response of Ultra-Thick CFRP Laminates"],"prefix":"10.3390","volume":"18","author":[{"given":"Yue","family":"Chen","sequence":"first","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xu","family":"Liang","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liqun","family":"Tian","sequence":"additional","affiliation":[{"name":"Shanghai Marine Equipment Research Institute, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8802-6800","authenticated-orcid":false,"given":"Baoxuan","family":"Wang","sequence":"additional","affiliation":[{"name":"Ocean College, Zhejiang University, Zhoushan 316021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Wang","sequence":"additional","affiliation":[{"name":"Donghai Laboratory, Zhoushan 316021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Titao","family":"Wang","sequence":"additional","affiliation":[{"name":"Shanghai Marine Equipment Research Institute, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1016\/j.compstruct.2009.08.010","article-title":"Fracture Mechanisms and Failure Analysis of Carbon Fibre\/Toughened Epoxy Composites Subjected to Compressive Loading","volume":"92","author":"Jumahat","year":"2010","journal-title":"Compos. Struct."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"107706","DOI":"10.1016\/j.compscitech.2019.107706","article-title":"Compressive Fracture Aspect of Thick Quasi-Isotropic Carbon Fiber Reinforced Plastic Laminates","volume":"181","author":"Goto","year":"2019","journal-title":"Compos. Sci. Technol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1023\/A:1018640015465","article-title":"Size Effect on Compression Strength of Fiber Composites Failing by Kink Band Propagation","volume":"95","author":"Kim","year":"1999","journal-title":"Int. J. Fract."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Greenhalgh, E.S. (2009). 3\u2014Fibre-Dominated Failures of Polymer Composites. Failure Analysis and Fractography of Polymer Composites, Woodhead Publishing. Woodhead Publishing Series in Composites Science and Engineering.","DOI":"10.1201\/9781439847510-c3"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2653","DOI":"10.1016\/S0020-7683(00)00175-X","article-title":"On the Initiation and Growth of Kink Bands in Fiber Composites. Part II: Analysis","volume":"38","author":"Vogler","year":"2001","journal-title":"Int. J. Solids Struct."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.compositesa.2018.12.017","article-title":"Compressive Failure of Fiber Reinforced Polymer Composites by Imperfection","volume":"118","author":"Yuan","year":"2019","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"118818","DOI":"10.1016\/j.compstruct.2024.118818","article-title":"An Experimental Investigation of the Compressive Failure in Quasi-Isotropic Ultra-Thick CFRP Laminates","volume":"354","author":"Chen","year":"2025","journal-title":"Compos. Struct."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"107966","DOI":"10.1016\/j.ijmecsci.2022.107966","article-title":"Investigation on the Compressive Mechanical Properties of Ultra-Thick CFRP Laminates","volume":"241","author":"Gao","year":"2023","journal-title":"Int. J. Mech. Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1016\/0010-4361(90)90343-U","article-title":"Failure Modes of Unidirectional Carbon\/Epoxy Composite Compression Specimens","volume":"21","author":"Odom","year":"1990","journal-title":"Composites"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"543","DOI":"10.1016\/1359-8368(95)00010-0","article-title":"Failure Mechanisms in Thick Composites under Compressive Loading","volume":"27","author":"Daniel","year":"1996","journal-title":"Compos. Part B Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1789","DOI":"10.1177\/002199839502901307","article-title":"A New Compression Test Method for Thick Composites","volume":"29","author":"Hsiao","year":"1995","journal-title":"J. Compos. Mater."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"108390","DOI":"10.1016\/j.ijmecsci.2023.108390","article-title":"Thickness Variation Effect on Compressive Properties of Ultra-Thick CFRP Laminates","volume":"253","author":"Gao","year":"2023","journal-title":"Int. J. Mech. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2015","DOI":"10.1016\/j.compscitech.2006.12.001","article-title":"A Study on the Compressive Strength of Thick Carbon Fibre\u2013Epoxy Laminates","volume":"67","author":"Lee","year":"2007","journal-title":"Compos. Sci. Technol."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Yu, Y., Pan, Y., Zhou, R., and Miao, X. (2021). Effects of Water and Alkaline Solution on Durability of Carbon-Glass Hybrid Fiber Reinforced Polymer Bars. Polymers, 13.","DOI":"10.3390\/polym13213844"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"115719","DOI":"10.1016\/j.compstruct.2022.115719","article-title":"Mechanical Performance Evolution and Life Prediction of Prestressed CFRP Plate Exposed to Hygrothermal and Freeze-Thaw Environments","volume":"293","author":"Xian","year":"2022","journal-title":"Compos. Struct."},{"key":"ref_16","unstructured":"(2003). Standard Test Method for Compressive Properties of Polymer Matrix Composite Materials with Unsupported Gage Section by Shear Loading (Standard No. D3410\/D3410M-03)."},{"key":"ref_17","unstructured":"(2014). Standard Test Method for Compressive Properties of Polymer Matrix Composite Materials Using a Combined Loading Compression (CLC) Test Fixture (Standard No. D6641\/D6641M-14)."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1080\/09243046.2016.1226689","article-title":"A Simple Test Method, NAL-II, to Evaluate the Strength and Elastic Modulus of Polymer Matrix Composite Laminates","volume":"25","author":"Ogasawara","year":"2016","journal-title":"Adv. Compos. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1520\/CTR10469J","article-title":"Effect of Specimen Tab Configuration on Compression Testing of Composite Materials","volume":"17","author":"Xie","year":"1995","journal-title":"J. Compos. Technol. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1217","DOI":"10.1177\/073168449601501203","article-title":"Influence of Unidirectional Composite Compression Specimen Thickness and Loading Method","volume":"15","author":"Xie","year":"1996","journal-title":"J. Reinf. Plast. Compos."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.compscitech.2019.05.007","article-title":"Influence of Tab Debonding on Measured Stiffness Evolution in Compression-Compression and Tension-Compression Fatigue Testing of Short Gauge Length Coupons","volume":"180","author":"Sevenois","year":"2019","journal-title":"Compos. Sci. Technol."},{"key":"ref_22","unstructured":"Schwartz, R.T., and Schwartz, H.S. (1968). Strength Theories of Filamentary Structures. Fundamental Aspects of Fiber Reinforced Plastic Composites, Interscience Publishers."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1177\/002199837100500106","article-title":"A General Theory of Strength for Anisotropic Materials","volume":"5","author":"Tsai","year":"1971","journal-title":"J. Compos. Mater."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"448","DOI":"10.1177\/002199837300700404","article-title":"A Fatigue Failure Criterion for Fiber Reinforced Materials","volume":"7","author":"Hashin","year":"1973","journal-title":"J. Compos. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1115\/1.3153664","article-title":"Failure Criteria for Unidirectional Fiber Composites","volume":"47","author":"Hashin","year":"1980","journal-title":"J. Appl. Mech."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1045","DOI":"10.1016\/S0266-3538(96)00140-6","article-title":"Failure Analysis of FRP Laminates by Means of Physically Based Phenomenological Models","volume":"58","author":"Puck","year":"1998","journal-title":"Compos. Sci. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2313","DOI":"10.1177\/0021998312454478","article-title":"Material and Structural Response of Polymer-Matrix Fibre-Reinforced Composites","volume":"46","author":"Pinho","year":"2012","journal-title":"J. Compos. Mater."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1016\/0266-3538(88)90043-7","article-title":"Role of Matrix Resin in Delamination Onset and Growth in Composite Laminates","volume":"33","author":"Ye","year":"1988","journal-title":"Compos. Sci. Technol."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/19\/2342\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T08:22:04Z","timestamp":1790324524000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/19\/2342"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,25]]},"references-count":28,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2026,10]]}},"alternative-id":["polym18192342"],"URL":"https:\/\/doi.org\/10.3390\/polym18192342","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,25]]}}}