http://hdl.handle.net/10174/15 Tue, 23 Jun 2026 07:46:15 GMT 2026-06-23T07:46:15Z http://hdl.handle.net/10174/42222 Title: Physical-Mechanical Changes in Portuguese, Greek, and Italian Marbles Under Aging Cycles Simulating Environmental Effects Linked to Bowing Authors: Pires, Vera; Sitzia, Fabio; Dias, Luis; Mirao, Jose; Neves, Samuel Abstract: Bowing, a significant form of decay, poses a crucial chal- lenge in the preservation of historical and contempo- rary structures, requiring comprehensive study and anal- ysis. This research focuses on the mechanical alterations induced by aging cycles of temperature and moisture on three distinct marbles (Portuguese, Greek, and Italian) emphasizing their susceptibility to bowing-associated effects. The prevalence of bowing in prominent histor- ical buildings underscores the urgency of understanding its underlying mechanisms and mitigating its impact. Through 50 aging cycles, this investigation discerns the distinct behaviors and properties exhibited by each marble, providing invaluable insights into the complex interac- tion between geological composition and environmental stressors. By highlighting the relevance of bowing and its detrimental effects on architectural heritage, this study underscores the importance of proactive measures in conservation and restoration efforts. Mon, 29 Sep 2025 23:00:00 GMT http://hdl.handle.net/10174/42222 2025-09-29T23:00:00Z http://hdl.handle.net/10174/42221 Title: Trentepohlia Algae as a Diagnostic Tool for Historic Mediterranean—Style Houses Authors: Sitzia, Fabio; Pires, Vera; Lisci, Carla; Neves, Samuel; Mirao, Josè Abstract: Trentepohlia is a genus of filamentous chlorophytes green algae commonly found in association with fungi and bacteria on building envelopes. Their colonies have a char- acteristic red coloration which results from the produc- tion of β-carotene and hematochrome pigments. They are commonly present on walls, roofs and other external building structures and thrive in humid and shaded envi- ronments where sufficient moisture is available. Since their growth is strongly influenced by factors such as water availability, time of wetness, substrate temperature, and lighting conditions, the distribution is usually non-uniform and reflects the varying moisture exposure across different parts of a building. Usually, Trentepohlia prevails in areas affected by water rebound, runoff, splashing, capillary rising or accidental water leaks. Moreover, Trentepohlia spotlights intervention restorations done by materials with different thermal conductivity and hygroscopic proper- ties. Given that water is one of the most damaging factors affecting building performance, these algae can serve as valuable bioindicators for detecting the most moisture-affected areas. In this work many case studies regarding tracer properties of Trentepohlia algae will be shown in association with building’s 3D reconstruction, Building Information Modeling, thermal imaging survey and chemical-physical analysis of the growing substrates. Mon, 29 Sep 2025 23:00:00 GMT http://hdl.handle.net/10174/42221 2025-09-29T23:00:00Z http://hdl.handle.net/10174/42220 Title: Colour Stability of Light-Sensitive Minerals Under UVA340nm Irradiation: Implications for the Conservation of Cultural Heritage and Museum Display Conditions Authors: Sitzia, Fabio; Moita, Patricia; Scardina, Silvia; Lisci, Carla Abstract: Several minerals are known to undergo chromatic variations when exposed to sunlight, particularly ultraviolet (UV) radiation. These phases, defined as photosensitive, exhibit colour change due to photochemical reactions. To understand this phenomenon, this study investigates the colour alteration in 26 common mineral phases, aiming to better understand their behaviour under artificial ageing conditions. Each mineral was firstly chemically characterised by SEM-EDS to identify common chromophoric impurities. Subsequently, samples were exposed to UV radiation in the climatic chamber. The colour shifts were semi-quantitatively assessed in the CIEL*a*b* colour space after ageing. The results indicate that just 4 minerals out of 26 display negligible colour variation, whereas 22 show evident colour changes. These findings highlight the vulnerability of photosensitive minerals to UV-induced colour changes and raise concerns regarding their behaviour in artworks, historical surfaces, and cultural heritage objects. As such minerals are frequently found in the heritage field, understanding their photochemical responses is essential for developing informed preventive conservation strategies, particularly concerning light exposure in both museum and outdoor contexts. Sun, 02 Feb 2025 00:00:00 GMT http://hdl.handle.net/10174/42220 2025-02-02T00:00:00Z http://hdl.handle.net/10174/42156 Title: PARECER GEOTÉCNICO Instabilização de muro de suporte - Lote 5, Vale da Arrancada, Portimão Authors: faria, Paula Abstract: Parecer geotécnico sobre a instabilização de um muro de suporte situado no Vale da Arrancada, Lote 5, em Portimão, ocorrida a 26 de Novembro de 2020. Mon, 17 Mar 2025 00:00:00 GMT http://hdl.handle.net/10174/42156 2025-03-17T00:00:00Z