http://hdl.handle.net/10174/14475 2026-04-03T23:43:14Z http://hdl.handle.net/10174/39990 Title: Walls of the Castle of Alcácer do Sal – Contribution to the Study of Mortars in Military Architecture Authors: Almeida, M; Pinheiro-Alves, T; Moita, Patrícia; Galacho, Cristina Abstract: The strategic location of Alcácer do Sal, on the banks of the Sado River and in a region rich in natural resources, explains the various occupations of this territory throughout history. However, it was the influence of the Muslim occupation (715–1217) that stood out the most, still visible today through archaeological remains, the town’s name, and, in this case study, the castle walls (11th–12th centuries), which have undergone several interventions over time. A visual inspection of the walls was conducted to assess their current condition. This revealed that the main causes of deterioration are related to water infiltration due to insufficient maintenance, lack of proper drainage, and the absence of protective elements such as coping. These issues have led to the loss of render adhesion, biological colonization, and material disintegration in several areas. The mortar samples were characterized using a multi-analytical approach, including Optical Microscopy (stereo zoom and petrographic microscope), X-ray Diffraction, Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy, Thermogravimetric Analysis, acid attack, and granulometric analysis. The results indicate that the mortars have similar compositions in terms of raw materials and likely provenance. An intervention strategy was proposed to address the identified pathologies and support future conservation efforts. 2025-09-30T23:00:00Z http://hdl.handle.net/10174/39981 Title: Tracing Construction Phases at the Roman Villa Horta da Torre (Fronteira, Portugal): Insights from mortars aggregate s Authors: Takahashi, Mizuki; Galacho, Cristina; Carneiro, André; Moita, Patrícia Abstract: The Roman villa Horta da Torre, built around 3 th 4 th century A.D., is located at Cabeço de Vide (Fronteira, Portugal). To address the construction(s) phase(s), production technolo gy and provenance of materials, a total of 18 samples of mortar walls were collected from Horta da Torre,including renders and fillers. A multi analytical approach to study textural, and mineralogical features of the selected mortars was developed Th is w ork suggests the existence of three construction phases based on their aggregates; gabbroic, granitic, and mixed, used as filling and render at the excavated pars urbana of the villa. study also revealed that the aggregates likely come from two local sourc es; gabbroic river sand from 2 km north of the site and granitic quarry/outcrops 3.5 km south of the site, whereas calcitic lime raw material was available at a distance of within a kilometer of the site 2025-09-30T23:00:00Z http://hdl.handle.net/10174/38860 Title: Exploring Antimicrobial Activity of Pristine Environment Bacterial Extracts Against Biodeteriogenic Microorganisms. Authors: Gatinho, Patrícia; Salvador, Cátia; Miller, Ana; Caldeira, Ana Teresa Editors: Laranjo, Marta; Alexandre, Ana; Medronho, Bruno; Eufrázio, Sofia; Marques, Cláudia; Pinto Correia, Teresa Abstract: Biodeterioration caused by biodeteriogenic microorganisms is a significant challenge for the preservation of Cultural Heritage. These microorganisms can harm important artworks, monuments, and historical sites, leading to their deterioration over time. Traditional methods to combat this issue often rely on biocides, which are chemical agents that kill or inhibit these harmful organisms. However, many biocides are highly toxic and can have negative effects on the environment and living organisms, making it essential to find safer alternatives. One promising solution is to use bioactive metabolites produced by bacteria found in pristine environments. These unique bacteria have evolved to survive in extreme conditions, and they produce antimicrobial compounds that help them fend off other microorganisms. By tapping into these natural compounds, we can create biocontrol agents that are less harmful to the environment and effective against the microorganisms that threaten Cultural Heritage. The bioactive metabolites from these bacteria can inhibit the growth of competing microorganisms, thus protecting valuable cultural sites. This method could lead to the development of green-safe biocides agents that are both effective and environmentally friendly. By investigating the potential of these natural products, we can make important advances in bioremediation. Exploring bioactive metabolites from bacteria to combat biodeterioration is a promising direction for future efforts. This method offers a safer and more sustainable approach to preserving Cultural Heritage while also benefiting other sectors, showcasing the potential of nature in solving modern challenges. 2024-12-01T00:00:00Z http://hdl.handle.net/10174/38859 Title: From Biofilms to Preservation: Addressing Microbial-Induced Stone Discoloration at Batalha Monastery Authors: Silva, Inês; Salvador, Cátia; Miller, Ana; Candeias, António; Caldeira, Ana Teresa Editors: Laranjo, Marta; Alexandre, Ana; Medronho, Bruno; Eufrázio, Sofia; Marques, Cláudia; Pinto Correia, Teresa Abstract: Throughout history, stone has been a preferred material for the construction of iconic structures due to its aesthetic appeal and intrinsic properties. However, like other construction materials, stone is subject to continuous deterioration by microorganisms, making its preservation critical for the protection of cultural heritage. Batalha Monastery (Portugal), a UNESCO World Heritage Site, exhibits notable surface alterations in the stone architectural elements of both the Founder's Chapel and the church, including extensive pink discoloration affecting the walls and columns. The use of both culturedependent and -independent methods for identifying the colonizing microbiota indicated that the main microorganisms forming the observed biofilms were the bacterial genera Halalkalicoccus, Bacillus, Gordonia, Serratia, and Methylobacterium. In this study, one of the bacterial isolates identified in the stone, from the genus Gordonia, was selected to carry out biocolonization tests on limestone, aiming to mimic the discoloration process observed in the monument. Two stone mock-ups were prepared, one kept in darkness and the other exposed to sunlight, to compare the bacterial behavior under different light conditions. Colorimetry and RAMAN spectroscopy techniques were employed, allowing for the in-situ characterization of color changes and pigments produced by the isolate. Furthermore, cleaning tests were also carried out on the mock-ups, in an attempt to remove the carotenes produced. The results from the aforementioned techniques revealed that the bacteria used in the tests, induced significant colorimetric changes in the stone. These changes were more pronounced when the stone was exposed to sunlight compared to those observed under dark conditions. In addition, the results of the cleaning tests demonstrated that the concentrations of the cleaning solution used are highly effective in removing pigments and can safely be suitable for heritage use.In order to prevent the deterioration of this cultural asset and ensure its preservation, we consider this study to be a critical step towards formulating a precise and effective conservation and intervention strategy for the Batalha Monastery. 2024-12-01T00:00:00Z