{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,26]],"date-time":"2026-04-26T16:38:01Z","timestamp":1777221481741,"version":"3.51.4"},"reference-count":77,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,30]],"date-time":"2023-11-30T00:00:00Z","timestamp":1701302400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER funds","award":["UIDB\/00285\/2020"],"award-info":[{"award-number":["UIDB\/00285\/2020"]}]},{"name":"FEDER funds","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}]},{"DOI":"10.13039\/501100001871","name":"CEMMPRE funding","doi-asserted-by":"publisher","award":["UIDB\/00285\/2020"],"award-info":[{"award-number":["UIDB\/00285\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"CEMMPRE funding","doi-asserted-by":"publisher","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"ARISE funding","doi-asserted-by":"publisher","award":["UIDB\/00285\/2020"],"award-info":[{"award-number":["UIDB\/00285\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"ARISE funding","doi-asserted-by":"publisher","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The present work focuses on the further development of a new family of geopolymers obtained by the alkaline activation of a binder. The aim is to find a viable alternative to concrete that can be used in civil construction. Regarding the influence of the curing temperature on this type of mixture, the recommendations in the existing literature are different for fly ash, ground granulated blast-furnace slag, and metakaolin-based geopolymers. While for fly ash and slag, increasing the curing temperature above 60 \u00b0C is reported to be advantageous, for metakaolin geopolymers, the opposite is reported. In this context, the objective of this work is to evaluate the mechanical strength of several metakaolin-based geopolymer specimens subjected to different curing temperatures (10, 15, 20, 30, 40 and 50 \u00b0C). Furthermore, several stress-strain diagrams are also shown. Based on the results, we recommend using curing temperatures below 30 \u00b0C in order to avoid reducing the strength of metakaolin-based geopolymers. Curing at 50 \u00b0C, relative to room temperature, results in a reduction of more than 35% in flexural strength and a reduction of more than 60% in compressive strength. Regarding the behavior of the geopolymers, it was found that the strain, at the ultimate stress, is about 2 to 2.5 times the strain of an equivalent cement mortar.<\/jats:p>","DOI":"10.3390\/ma16237460","type":"journal-article","created":{"date-parts":[[2023,11,30]],"date-time":"2023-11-30T09:39:12Z","timestamp":1701337152000},"page":"7460","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Influence of Curing Temperature on the Strength of a Metakaolin-Based Geopolymer"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5092-4891","authenticated-orcid":false,"given":"Adelino","family":"Lopes","sequence":"first","affiliation":[{"name":"INESC Coimbra, Department of Civil Engineering, University of Coimbra, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8101-7095","authenticated-orcid":false,"given":"S\u00e9rgio","family":"Lopes","sequence":"additional","affiliation":[{"name":"CEMMPRE, ARISE, Department of Civil Engineering, University of Coimbra, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2325-5108","authenticated-orcid":false,"given":"Isabel","family":"Pinto","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, University of Coimbra, 3030-788 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,30]]},"reference":[{"key":"ref_1","unstructured":"Teixeira-Pinto, A. 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