{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T19:43:52Z","timestamp":1768592632667,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,7,4]],"date-time":"2024-07-04T00:00:00Z","timestamp":1720051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Science and Technology Foundation","award":["SFRH\/BD\/07370\/2021"],"award-info":[{"award-number":["SFRH\/BD\/07370\/2021"]}]},{"name":"Portuguese Science and Technology Foundation","award":["CEECIND\/04583\/2017\/CP1399\/CT0003"],"award-info":[{"award-number":["CEECIND\/04583\/2017\/CP1399\/CT0003"]}]},{"name":"Portuguese Science and Technology Foundation","award":["UIDB\/04708\/2020"],"award-info":[{"award-number":["UIDB\/04708\/2020"]}]},{"name":"Base Funding","award":["SFRH\/BD\/07370\/2021"],"award-info":[{"award-number":["SFRH\/BD\/07370\/2021"]}]},{"name":"Base Funding","award":["CEECIND\/04583\/2017\/CP1399\/CT0003"],"award-info":[{"award-number":["CEECIND\/04583\/2017\/CP1399\/CT0003"]}]},{"name":"Base Funding","award":["UIDB\/04708\/2020"],"award-info":[{"award-number":["UIDB\/04708\/2020"]}]},{"name":"CONSTRUCT\u2014Instituto de I&amp;D em Estruturas e Constru\u00e7\u00f5es","award":["SFRH\/BD\/07370\/2021"],"award-info":[{"award-number":["SFRH\/BD\/07370\/2021"]}]},{"name":"CONSTRUCT\u2014Instituto de I&amp;D em Estruturas e Constru\u00e7\u00f5es","award":["CEECIND\/04583\/2017\/CP1399\/CT0003"],"award-info":[{"award-number":["CEECIND\/04583\/2017\/CP1399\/CT0003"]}]},{"name":"CONSTRUCT\u2014Instituto de I&amp;D em Estruturas e Constru\u00e7\u00f5es","award":["UIDB\/04708\/2020"],"award-info":[{"award-number":["UIDB\/04708\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Infrastructures"],"abstract":"<jats:p>Railway lines require a significant amount of natural raw materials. Industrial by-products can be used instead, reducing the costs of natural aggregate exploration. This work analyzes a ballasted track\u2019s short- and long-term performances when replacing conventional sub-ballast aggregate with steel slag. After an extensive laboratory characterization of the steel slag, the material performance was analyzed in a 3D numerical model of a ballasted track when included in a railway track. An empirical model was implemented and calibrated to predict the long-term permanent deformation induced in the track after many train passages. The results are compared with the allowable deformation limits required for conventional high-speed ballasted track railway lines. An additional analysis was conducted to assess the influence of steel slags on the critical speed of conventional railway tracks when used. The results show a residual impact on the critical speed value compared to the conventional sub-ballast made with natural aggregates.<\/jats:p>","DOI":"10.3390\/infrastructures9070106","type":"journal-article","created":{"date-parts":[[2024,7,4]],"date-time":"2024-07-04T06:28:54Z","timestamp":1720074534000},"page":"106","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Steel Slag Sub-Ballast for Sustainable Railway Track Infrastructure"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6249-1787","authenticated-orcid":false,"given":"Rubens","family":"Alves","sequence":"first","affiliation":[{"name":"CONSTRUCT-GEO, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Federal Institute of Education, Science and Technology of Rio Grande do Norte (IFRN), Av. Sen. Salgado Filho, 1559, Natal 59015-000, RN, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8381-0126","authenticated-orcid":false,"given":"Ana","family":"Ramos","sequence":"additional","affiliation":[{"name":"CONSTRUCT-LESE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"}]},{"given":"Alexandre","family":"Castanheira-Pinto","sequence":"additional","affiliation":[{"name":"CONSTRUCT-GEO, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2625-1452","authenticated-orcid":false,"given":"Sara","family":"Rios","sequence":"additional","affiliation":[{"name":"CONSTRUCT-GEO, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6201-4235","authenticated-orcid":false,"given":"Jes\u00fas","family":"Fern\u00e1ndez-Ruiz","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, University of A Coru\u00f1a, Campus de Elvi\u00f1a, s\/n, 15008 A Coru\u00f1a, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.trgeo.2020.100326","article-title":"Mechanistic-Empirical Permanent Deformation Models: Laboratory Testing, Modelling and Ranking","volume":"23","author":"Ramos","year":"2020","journal-title":"Transp. 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