Guia Termos de Referência de Isolamento Acústico na Reabilitação de Edifícios

Mestrado em Engenharia Civil – Ramo de Construções

Uranium glass in museum collections

Journal of Cultural Heritage, nº 9 (2008), p. 64-68

Efficiency of strengthening techniques assessed for existing masonry buildings

The Azores archipelago is a zone with a vast cultural heritage, presenting a building stock mainly constructed in traditional stone masonry. It is known that this type of construction exhibits poor behaviour under seismic excitations; however it is extensively used in seismic prone areas, such as this case. The 9th of July of 1998 earthquake was the last seismic event in the islands, leaving many traditional stone constructions severely damaged or totally destroyed. This scenario led to an effort by the local government of improving the seismic resistance of these constructions, with the application of several reinforcement techniques. This work aims to study some of the most used reinforcement schemes after the 1998 earthquake, and to assess their effectiveness in the mitigation of the construction’s seismic vulnerability. A brief evaluation of the cost versus benefit of these retrofitting techniques is also made, seeking to identify those that are most suitable for each building typology. Thus, it was sought to analyze the case of real structures with different geometrical and physical characteristics, by establishing a comparison between the seismic performance of reinforced and non-reinforced structures. The first section contains the analysis of a total of six reinforcement scenarios for each building chosen. Using the recorded 1998 earthquake accelerograms, a linear time-history analysis was performed for each reinforcement scenario. A comparison was then established between the maximum displacements, inter-storey drift and maximum stress obtained, in order to evaluate the global seismic response of each reinforced structure. In the second part of the work, the examination of the performance obtained in the previous section, in relation to the cost of implementing each reinforcement technique, allowed to draw conclusions concerning the viability of implementing each reinforcement method, based on the book value of the buildings in study.

Comparative evaluation of aerial lime mortars for architectural conservation

Journal of Cultural Heritage 9 (2008) 338-346

InStory – The Making of na Interactive Digital Narrative

Em cooperação com Glorianna Davenport do M.I.T. Media Lab

A private library in the Mateus Palace (Vila Real). The D. Luís António de Sousa Botelho Mourão (1722-1798) Books Collection

Fundação para a Ciência e Tecnologia no âmbito de Bolsa de Doutoramento (SFRH/BD/86280/2012)

Analysis and treatment of a nineteenth century oil painting

This thesis focused on the study and treatment of a 19th century female portrait in oil from ECOMUSEU Municipal do Seixal, Portugal. The portrait, which depicts Isabel Maria Lourenço Affonso was in poor condition and a large strip of paint and canvas was missing (approximately 9cm by 66cm, almost 11% of the total surface area). The portrait is a companion piece to a male portrait (the relationship was established as part of this study), therefore a technical study of both paintings was considered essential to support the choices made during the treatment. The project involved three main areas: - The study of the history, condition, materials and techniques of both paintings. This allowed their comparison and understanding of their relationship; - The treatment of Isabel Maria Lourenço Affonso. The choices made and problems encountered are described. - The production of a replacement for the missing strip of paint and canvas. The practical solution developed to overcome such an unusual challenge is described along with the creative and flexible thinking required. Because not all traditional infill materials cope well on a mechanical level with thin layers over a very large surface (many are too brittle), strict criteria had to be employed to choose the appropriate material. The primary goal was to find a fill which would remain flexible and be capable of accepting surface texture, such that there would be a good visual match with the painting. Analysis and testing was carried out to evaluate the physical properties of the fill material chosen, BEVA® Gesso-P. The successful creation of the replacement strip has resulted in two publications and one presentation: Publication pending in The Picture Restorer, Leslie Carlyle, Raquel Marques, Isabel Pombo Cardoso and Sara Babo, “Creating a Textured Replacement Strip for the Missing Lower Portion of an Oil Portrait: Problem Solving and Practical Solutions”. Abstract accepted for presentation and publication, International Meeting on Retouching of Cultural Heritage (2RECH), Raquel Marques, Leslie Carlyle and Isabel Pombo Cardoso, “Textured Replacement Strip for a Missing Portion of a Portrait: Problem Solving and Practical Solutions”.

Evaluation of mechanical soft-abrasive blasting and chemical cleaning methods on alkyd-paint graffiti made on carbonate stones

In the context of this dissertation several studies were developed resulting in submission and publication “Evaluation of mechanical soft-abrasive blasting and chemical cleaning methods on alkyd-paint graffiti made on calcareous stones” to Journal of Cultural Heritage. (http://dx.doi.org/10.101 /j.culher.2014.10.004)

Biological colonization on majolica glazed tiles: biodeterioration, bioreceptivity and mitigation strategies

The impact of microbial activity on the deterioration of cultural heritage is a well-recognized global problem. Glazed wall tiles constitute an important part of the worldwide cultural heritage. When exposed outdoors, biological colonization and consequently biodeterioration may occur. Few studies have dealt with this issue, as shown in the literature review on biodiversity, biodeterioration and bioreceptivity of architectural ceramic materials. Due to the lack of knowledge on the biodeteriogens affecting these assets, the characterization of microbial communities growing on Portuguese majolica glazed tiles, from Pena National Palace (Sintra, Portugal) and another from Casa da Pesca (Oeiras, Portugal) was carried out by culture and molecular biology techniques. Microbial communities were composed of microalgae, cyanobacteria, bacteria and fungi, including a new fungal species (Devriesia imbrexigena) described for the first time. Laboratory-based colonization experiments were performed to assess the biodeterioration patterns and bioreceptivity of glazed wall tiles produced in laboratory. Microorganisms previously identified on glazed tiles were inoculated on pristine and artificially aged tile models and incubated under laboratory conditions for 12 months. Phototrophic microorganisms were able to grow into glaze fissures and the tested fungus was able to form oxalates over the glaze. The bioreceptivity of artificially aged tiles was higher for phototrophic microorganisms than pristine tile models. A preliminary approach on mitigation strategies based on in situ application of commercial biocides and titanium dioxide (TiO2) nanoparticles on glazed tiles demonstrated that commercial biocides did not provide long term protection. In contrast, TiO2 treatment caused biofilm detachment. In addition, the use of TiO2 thin films on glazed wall tiles as a protective coating to prevent biological colonization was analysed under laboratorial conditions. Finally, conservation notes on tiles exposed to biological colonization were presented.

Analysis and Treatment of a male portrait in oil and a study of the size layer with reconstructions from Vibert’s recipe (1892)

This thesis project concentrated on both the study and treatment of an early 20th century male portrait in oil from Colecção Caixa Geral de Depósitos, Lisbon, Portugal. The portrait of Januário Correia de Almeida, exhibits a tear (approximately 4.0 cm by 2.3 cm) associated with paint loss on the right upper side, where it is possible to observe an unusually thick size layer (approximately 50 microns) and an open weave mesh canvas. Size layers made from animal glue remain subject to severe dimensional changes due to changes in relative humidity (RH), thereby affecting the stability of the painting. In this case, the response to moisture of the size layer is minimal and the painting is largely uncracked with very little active flaking. This suggests that the size layer has undergone pre-treatment to render it unresponsive to moisture or water. Reconstructions based on late nineteenth century recipes using historically appropriate materials are used to explore various options for modifying the characteristics of gelatine, some of which may relate to the Portrait’s size layer. The thesis is separated into two parts: Part 1: Describes the history, condition, materials and techniques of the painting. It also details the treatment of Januário Correia de Almeida as well as the choices made and problems encountered during the treatment. Part 2: Discusses the history of commercial gelatine production, the choice of the appropriate animal source to extract the collagen to produce reconstructions of the portrait’s size layer as well as the characterization of selected reconstructions. The execution of a shallow textured infill led to one publication and one presentation: Abstract accepted for presentation and publication, International Meeting on Retouching of Cultural Heritage (RECH3), Francisco Brites, Leslie Carlyle and Raquel Marques, ‘’Hand building a Low Profile Textured Fill for a Large Loss’’.

Objects that move: Japanese Namban screens in the realm of the senses

This paper identifies and critiques the value of stillness as a necessary condition for the display and appreciation of art objects like the 16th century Japanese Namban screens, whose history and function is characterised by forms of movement. Drawing on multi-sited fieldwork in museum galleries that display these screens in Japan, Portugal and North America I will detail how the art-historical interpretation of the physical passage of these objects and their value as cultural heritage is based upon the fixed point perspectivism of networks and a visualist paradigm. Museum focused processes of conservation and display can be understood as extending this paradigm. By means of environmental controls, directed towards the location of perceptible meaning in what is available to vision and the necessary attenuation of the other senses the material movements of the object and movements of constituent materials in the object are stilled. The argument is for a sensory approach to museums and the objects within them, which in this case takes account of the material movements of the screens by engaging the senses through the ‘touch of sound’ as well as vision.

Gestão de museus : o caso do Museu Nacional de Arqueologia

O presente trabalho pretende caraterizar o regime atual de governação do MNA descrevendo-o do ponto de vista dos recursos financeiros, recursos humanos, marketing e planeamento, tendo em conta a sua dependência da Direção Geral de Património Cultural, complementarmente pretende apresentar algumas propostas de melhoria. Desde a sua criação o Museu Nacional de Arqueologia, tem por objetivo representar a parte material da vida do homem português desde a pré-história. Hoje, constitui a instituição de referência da Arqueologia Portuguesa, ligado a outros museus, universidades e centros de investigação por todo o mundo. Num momento em que num número crescente de países, os museus e instituições culturais têm de procurar fontes alternativas de financiamento, por força do desinvestimento por parte dos Estados, e a reduzir os gastos, incluindo restrições às contratações de recursos humanos, coloca-se um grande desafio àqueles que gerem estas instituições. Por um lado, valências como lojas com artigos ligados ao museu e a concessão de espaços de restauração nas suas instalações, a organização de eventos temáticos lúdico-pedagógicos, acompanhados de uma estratégia de comunicação segmentada, contribuem para a diversificação e o aumento de públicos. Por outro lado, atividades de fundraising devem passar a ser uma prática comum nestas entidades. Tudo isto, tendo sempre presente que se trata de uma entidade cultural com uma função de produção de conhecimento e cultura, não devendo o Estado alhear-se desta função. O Museu Nacional de Arqueologia, é tutelado pela Direção Geral do Património Cultural o que impõe constrangimentos ao nível da gestão. Embora seja possível, pela direção do MNA, tomar decisões relativas à área financeira, a perceção do seu impacto não é imediata. No que respeita aos recursos humanos, estamos perante um quadro qualificado, capaz de dar resposta às exigências do funcionamento do museu, mas que pela média etária e pelas dificuldades de contratação, coloca em risco o futuro. O marketing e o planeamento são as áreas em análise que apresentam menos constrangimentos, pela dependência da tutela. Os processos de marketing são concretizados pelos diferentes departamentos, com uma abordagem tradicional, ou seja unilateral, verificando-se pouca interação com os seus públicos. O plano de atividades é bastante completo e é uma boa ferramenta de gestão no que respeita ao planeamento, assim como o planeamento de carácter estratégico permite ao museu seguir uma linha de continuidade.

Structural assessment of a masonry vault in Portugal

This paper reports on a structural safety assessment and performance evaluation of the upper choir of the Santa Maria de Belém Church in the Jerónimos monastery, Lisbon, one of the most important cultural heritage buildings in Portugal. The possibility of adding a new 20 t organ to the upper choir and its effects on the church structure's response are presented. A refined and a simplified finite-element model is developed to investigate the structure's performance under self-weight and seismic actions. A sensitivity analysis is performed to investigate the effect of masonry mechanical properties and rib cross-sections on the structural response, given the difficulty in accurately obtaining this information. The results show that the safety level of the structure is acceptable, even in the case of adding a heavy new organ.

Cost-effective and lightweight mobile units for MixAR: A comparative trial among different setups

Cultural heritage has arousing the interest of the general public (e.g. tourists), resulting in the increasing number of visitations to archaeological sites. However, many buildings and monuments are severely damaged or completely destroyed, which doesn’t allow to get a full experience of “travelling in time”. Over the years, several Augmented Reality (AR) approaches were proposed to overcome these issues by providing three-dimensional visualization of reconstructed ancient structures in situ. However, most of these systems were made available through heavy and expensive technological bundles. Alternatively, MixAR intends to be a lightweight and cost-effective Mixed Reality system which aims to provide the visualization of virtual ancient buildings reconstructions in situ, properly superimposed and aligned with real-world ruins. This paper proposes and compares different AR mobile units setups to be used in the MixAR system, with low-cost and lightweight requirements in mind, providing different levels of immersion. It was propounded four different mobile units, based on: a laptop computer, a single-board computer (SBC), a tablet and a smartphone, which underwent a set of tests to evaluate their performances. The results show that mobile units based on laptop computer and SBC reached a good overall performance while mobile units based on tablet and smartphone did not meet such a satisfactory result even though they are acceptable for the intended use.