{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T03:48:57Z","timestamp":1775101737181,"version":"3.50.1"},"reference-count":58,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,5]],"date-time":"2020-09-05T00:00:00Z","timestamp":1599264000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/ECI-COM-28308\/2017"],"award-info":[{"award-number":["PTDC\/ECI-COM-28308\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This paper intends to contribute to a better knowledge of the production and rehydration of thermoactivated recycled cement and its incorporation in cement-based materials. To this end, the influence of the treatment temperature on the properties of recycled cements and recycled cement pastes was assessed by means of a wide array of tests. Anhydrous recycled cement as well as the resulting pastes were characterized through density and particle size, water demand and setting time, thermogravimetry, X-ray diffraction, field emission gun scanning electron microscopy, isothermal calorimetry, 29Si nuclear magnetic resonance spectroscopy, flowability, mechanical strength, mercury intrusion porosimetry and scanning electron microscopy. The treatment temperature had a significant influence on the dehydration and hydration of recycled cement, essentially resulting in the formation of C2S polymorphs of varying reactivity, which led to pastes of different fresh and hardened behaviors. The high water demand and the pre-hydration of recycled cement resulted in high setting times and low compressive strengths. The highest mechanical strength was obtained for a treatment temperature of 650 \u00b0C.<\/jats:p>","DOI":"10.3390\/ma13183937","type":"journal-article","created":{"date-parts":[[2020,9,6]],"date-time":"2020-09-06T23:12:49Z","timestamp":1599433969000},"page":"3937","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":88,"title":["Influence of the Treatment Temperature on the Microstructure and Hydration Behavior of Thermoactivated Recycled Cement"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1546-9197","authenticated-orcid":false,"given":"Sofia","family":"Real","sequence":"first","affiliation":[{"name":"Civil Engineering Research and Innovation for Sustainability, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"given":"Ana","family":"Carri\u00e7o","sequence":"additional","affiliation":[{"name":"Civil Engineering Research and Innovation for Sustainability, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"given":"Jos\u00e9 Alexandre","family":"Bogas","sequence":"additional","affiliation":[{"name":"Civil Engineering Research and Innovation for Sustainability, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"given":"Mafalda","family":"Guedes","sequence":"additional","affiliation":[{"name":"Center for Product Development and Technology Transfer and Department of Mechanical Engineering, Set\u00fabal School of Technology, Instituto Polit\u00e9cnico de Set\u00fabal, 2910-761 Set\u00fabal, Portugal"},{"name":"Center of Physics and Engineering of Advanced Materials, Instituto Superior T\u00e9cnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"118873","DOI":"10.1016\/j.conbuildmat.2020.118873","article-title":"Thermoactivated cementitious materials\u2014A review","volume":"250","author":"Bogas","year":"2020","journal-title":"Constr. Build. Mater."},{"key":"ref_2","unstructured":"World Business Council for Sustainable Development and International Energy Agency (2009). Cement Technology Roadmap 2009. Carbon Emissions Reductions Up to 2050, International Energy Agency (IEA)."},{"key":"ref_3","unstructured":"Brito, J., and Saikia, N. (2013). 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