{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T08:02:48Z","timestamp":1769500968711,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,10,27]],"date-time":"2017-10-27T00:00:00Z","timestamp":1509062400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Infrastructures"],"abstract":"<jats:p>Today, the concrete sector is being pushed to innovate in order to better address current challenges with higher competitiveness and more sustainable solutions. Different research studies have been conducted all over the world in which novel approaches and paths were proposed. It is important to spread information to define new strategies for the future of this industry. The enhancement of concrete properties and the impact of these changes in structural design are some of the topics analysed in those studies. This paper presents four experimental studies conducted by the authors where different types of concrete and structural members were tested. The common goal of these studies was to develop innovative solutions with high performance and low environmental impact. The scope of the first study was the structural behaviour of members produced with lightweight aggregate concrete (LWAC). Results of several beams, ties, and slabs are herein presented and analysed. The advantage of using glass fibre\u2013reinforced polymer (GFRP) rebars was addressed in a second study, and main results obtained with this type of rebar are also herein presented. Recent advances in nanotechnology led to the development of concretes incorporating nanoparticles into the binder matrix. Typically, these nanoparticles have a diameter of 10\u2013300 nanometers and are added to the mixture to reduce the porosity and increase the density of the binder matrix, improving the mechanical properties and durability. To analyse their influence on steel-to-concrete bonding and on the shear and flexural behaviour of the beams was the main goal of the third study herein described. Finally, a new concept to produce reinforced concrete members with high durability using a special concrete cover, which was the goal of the fourth study, is also herein presented.<\/jats:p>","DOI":"10.3390\/infrastructures2040017","type":"journal-article","created":{"date-parts":[[2017,10,27]],"date-time":"2017-10-27T11:33:28Z","timestamp":1509104008000},"page":"17","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["New Trends for Reinforced Concrete Structures: Some Results of Exploratory Studies"],"prefix":"10.3390","volume":"2","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3254-2221","authenticated-orcid":false,"given":"Ricardo","family":"Carmo","sequence":"first","affiliation":[{"name":"CERIS and Polytechnic Institute of Coimbra, Rua Pedro Nunes\u2014Quinta da Nora, 3030-199 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1690-9887","authenticated-orcid":false,"given":"Eduardo","family":"J\u00falio","sequence":"additional","affiliation":[{"name":"CERIS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,27]]},"reference":[{"key":"ref_1","unstructured":"Costa, H., J\u00falio, E., and Louren\u00e7o, J. (2010, January 20\u201323). A New Mixture Design Method for Structural Lightweight Aggregate Concrete. Proceedings of the 8th Fib International PhD Symposium in Civil Engineering, Copenhagem, Denmark."},{"key":"ref_2","unstructured":"Costa, H., J\u00falio, E., and Louren\u00e7o, J. (2010, January 3\u20135). Lightweight Aggregate Concrete\u2014Codes Review and Needed Corrections. Proceedings of the Joint IABSE-Fib Conference on \u201cCodes in Structural Engineering\u201d, Dubrovnik, Croatia."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/j.conbuildmat.2015.10.066","article-title":"Critical review on eco-efficient ultra-high-performance concrete enhanced with nano-materials","volume":"101","author":"Ghafari","year":"2015","journal-title":"Constr. Build. 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