Mineralogical and chemical characterization of historical mortars from military fortifications in Lisbon harbour (Portugal)

• Autor(a) principal: Santos Silva, A.
• Data de Publicação: 2011
• Outros Autores: Cruz, T., Paiva, M.J., Candeias, A., Adriano, P., Schiavon, N., Mirão, J.P.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10174/4076; https://doi.org/Reference Type: Journal Article Author: Silva, A. Author: Cruz, T. Author: Paiva, M. Author: Candeias, A. Author: Adriano, P. Author: Schiavon, N. Author: Mirão, J. Primary Title: Mineralogical and chemical characterization of historical mortars from military fortifications in Lisbon harbour (Portugal) Journal Name: Environmental Earth Sciences Cover Date: 2011-08-01 Publisher: Springer Berlin / Heidelberg Issn: 1866-6280 Subject: Earth and Environmental Science Start Page: 1641 End Page: 1650 Volume: 63 Issue: 7 Url: http://dx.doi.org/10.1007/s12665-011-0985-0 Doi: 10.1007/s12665-011-0985-0; https://doi.org/10.1007/s12665-011-0985-0
• topic: historical mortars; Lisbon fortifications; PLM; TG-DTA; SEM-EDS; XRD

Abstract Historical mortars from sixteenth to seventeenth century military forts located at the mouth of the Tagus River in Lisbon have been characterized by polarized light microscopy (PLM), thermal analysis (TG/DTA), X-ray diffractometry (XRD) and scanning electron microscopy + energy dispersive spectroscopy (SEM + EDS). The results indicate that the mortars used were all hydraulic lime-based. The presence of well-rounded lime lumps indicates a limited use of water during the lime hydration process. The detection of hydrated calcium chloroaluminate and carboaluminate compounds mostly at binder-aggregate interfaces provides evidence for the onset of pozzolanic reactions during mortar production as further confirmed by the presence of ceramic fragments in the aggregate fractions intentionally added by the fort builders to increase the hydraulic properties of the mortars. The higher mechanical strength and greater resistance to degradation processes imparted by these pozzolanic compounds could explain why, despite the extreme proximity of the investigated sites to the sea, salt weathering processes do not appear to have significantly affected the studied mortars