Publications

Unstabilised rammed earth is a recyclable, economical and eco-friendly building material, used in the past and still applied today. Traditionally, its use was based on a long empirical knowledge of the local materials. Because this knowledge was mostly lost or is no longer sufficient, in many countries normative documents have been produced to allow the assessment of rammed earth soils. With the aim of contributing for a refining of these normative requirements, this article presents a research work that included: (i) collection of unstabilised rammed earth samples from six constructions in Portugal; (ii) a literature survey of normative and complementary documents to identify the most mentioned key-properties, the test procedures and the corresponding threshold limits; (iii) a discussion of the test procedures and of the thresholds limits in the light of the experimental results. The analyzed properties are the particle size distribution, maximum particle size, plasticity, compaction, linear shrinkage, organic content and salt content. The work highlights the advantages of taking into account the characteristics of existing constructions as a basis for the establishment and further refining of consistent threshold values. In particular, it shows that it is essential to adjust the requirements to the specificities of local materials.

It has long been thought that the evaporation rate from mesoporous materials during the constant drying rate period (CDRP) is equal to that of a free-water surface, due to the presence of a liquid film covering the surface of the material. In this article we review several early articles and demonstrate that the experimental scrutiny this hypothesis has received is insufficient. Further, we report a set of evaporative drying experiments on eight building materials whose results also do not confirm such hypothesis. Indeed, the drying rate during the CDRP is not equal either among the tested materials or between these and the free-water surfaces. To explain the differences in drying rate, we have looked at the influence of surface texture and porosity. We have concluded that surface texture, which could increase the effective surface area of the materials, did not have a relevant effect on the CDRP drying rate. However, we have found a good correlation between the CDRP drying rate and capillary porosity. This is consistent with the hypothesis that drying occurs at the pore level during the CDRP. Further, it contradicts the suggestion that there is a film of water covering the surface of the materials during this period.

Abstract. Shrinkage Reducing Admixtures (SRA) are being used more often in concrete structures in order to better control shrinkage cracks. High-performance concrete, nowadays with large application, has more proneness to crack at very early age due to the lower W/C. In this type of concrete, autogenous shrinkage is usually more important than drying shrinkage. Autogenous shrinkage is due to the volume decrease inherent to binder hydration reactions. The rate of these reactions is influenced not only by the type of binder but also by the presence of chemical admixtures. It is recognized that SRA delay the hydration, being a secondary effect of this type of admixtures. In this work changes on the degree of hydration of cement pastes with SRA and different binders are presented, using the chemical shrinkage test.

Dampness is a common condition in old buildings and, accordingly, many paint systems specific for this type of building allow for application on walls with nonnegligible moisture content. In spite of that, performance evaluation of these paints is normally carried out using dry substrates or even on free paint films. This article presents research performed on 16 commercial paint systems: seven silicate, three silicone, three hydro-pliolite and two lime-based systems, as well as one common vinyl emulsion paint that served as reference. Each paint was applied and cured both on dry and on damp mortar substrates. The test specimens were subjected to water vapor permeability tests and evaporative drying tests. The following conclusions could be drawn: (i) the way paint systems influence the drying of the substrate, to which they were applied and where they cured, may vary significantly depending on the moisture content of that substrate; (ii) vapor permeability, measured with specimens applied and cured on dry substrate, may be an acceptable way of predicting a paint’s influence on drying, provided that the paints are applied and cured on dry substrate or that their characteristics are not significantly affected by the moisture content of that substrate.

The management of construction and demolition waste (CDW) is essential in the formation, growth and renovation of urban areas. This paper presents part of a study on CDW generation and management in the Lisbon Metropolitan Area (LMA). CDW generation was estimated for 2006 and 2007 based on construction activity and waste load movements. The results revealed that in the municipality of Lisbon, remodeling construction activity prevailed, with CDW generation indicators of 954 t/day and a per capita rate of 0.60 t/year. Both values are above the average for the LMA and its two sub-regions (Greater Lisbon and the Setúbal Peninsula). The installed infrastructure for CDW management identified in the LMA is situated within a maximum distance of about 23 km from the geometric center of the city of Lisbon. Despite the fact these locations favor the municipality of Lisbon, the occurrence of illegal dumps is still a reality. A notable effort towards environmental education addressing CDW management is under way so as to make involved citizens aware of the recent CDW legislation, Decree-Law Nr. 46/2008, as well as of the problems arising from scenarios of environmental degradation and uncontrolled use of natural resources in the civil construction sector. Policies are outlined aiming to move towards the more judicious management of CDW.

Long-term durability of a structural adhesive joint is an important requirement, because it has to be able to support the required design loads, under service conditions, for the planned lifetime of the structure. Epoxy adhesives, whilst not ideal, are currently the best family of adhesives for in situ repair operations. As long as the bonded joint remains dry and unexposed to high service temperatures, epoxy adhesives produce strong bonds to timber. However, once they are exposed to severe stresses as a result of repeated water soaking and drying cycles, the bonded joint delaminates and does not fulfil the requirements for structural timber adhesives intended for exterior exposure. One way of improving bond durability is through the use of surface treatments prior to bonding. In this study, the effects of corona discharge surface treatment, hydroxymethylated resorcinol (HMR) and ?-glycidoxypropyltrimethoxysilane (GPMS) adhesion promoters on the durability enhancement of pine, iroko, and oak bonded joints were evaluated. The results proved that surface modification methods for adhesion promotion can be adapted to cellulosic substrates with significant improvements in bonded joint durability.

Epoxy adhesives have been used for many years in the rehabilitation of timber structures and are currently the most appropriate adhesive type for on-site operations. However, because they exhibit excellent initial joint strength when tested in standard climate conditions, there has not been a major concern about their service durability. In order to contribute to the ongoing discussion on the reliability of these adhesives, a study was conducted to evaluate the effect of environmental service conditions on the durability of four commercial two-component structural epoxy adhesives, as well as the effect that the type of mixing, curing and postcuring conditions, as well as the presence of moisture have on the adhesives viscoelastic properties. It was found that the preparation conditions, cure schedule and moisture have a significant effect on the performance of the bulk adhesives. Moreover, it was found that under ambient conditions there is potential for under-cure or slow progression of cure for the epoxy adhesive products typically employed in these applications, which in turn can compromise the durability of a bonded joint.

Adhesive bonding technology has played an essential role in the development and growth of the rehabilitation and repair of timber structures. The ability of a structural joint to maintain satisfactory long-term performance, often in severe environments, is an important requirement of a structural adhesive joint, as the joint should be able to support design loads, under service conditions, for the planned life time of the structure. A number of factors determining the durability of structural adhesive joints have been identified and can be grouped in three categories: environment, materials and stresses. The environment is dominated by temperature and moisture. The materials category includes the adherend, the adhesive, and the inter-phase between them both. The last category refers to the stresses to which the bond is subjected during or after exposure to service environment, affecting both longevity and residual strength. Since this subject in relation to timber bonding is very disperse within the literature, this paper will focus briefly on each of the aforementioned factors, thus providing a general understanding on the factors that influence the durability of bonded timber joints.

Long-term durability of a structural adhesive joint is an important requirement, because it has to be able to support the required design loads, under service conditions, for the planed lifetime of the structure. One way of improving bond durability is through the use of surface treatments prior to bonding, which will activate the adherends' surface, making it more receptive to the adhesive. In this study, the effects of two surface pre-treatments (corona discharge and flame ionization) on three timbers (maritime pine, iroko, and European oak) were evaluated quantitatively through contact angle measurements. These measurements allowed the determination of the changes in the timber surface thermodynamic characteristics, thus indicating which pre-treatment performed better. The results showed that both techniques increased each timber's surface free energy, which could translate into a durability enhancement of bonded joints. Overall, the corona-discharge treatment looks more promising, since this treatment leads to a bigger increase in the timber's surface energy, especially in its polar component, whilst also tended to be less species specific, less susceptible to variation, and the treatment effects lasted longer for this type of treatment.

The European Standard EN 13791 provides methodologies for estimating concrete compressive strength in structures. This standard covers the testing of cores as well as the use of indirect methods, such as the rebound hammer, USPV and pull-out tests. This communication refers to a study carried out in a building where the methodologies presented in EN 13791 has been applied to estimate the in-situ characteristic strength, based on a widened set of pairs of rebound hammer and core compressive strength test results. A statistical interpretation of the two alternatives provided by the standard for the establishment of the relationship between the in-situ strength and the rebound number is presented, and some relevant aspects related to the regression analysis not mentioned by the standard, such as the precision of the rebound number and the confidence level, are discussed.

Desde a segunda metade do século XVI que o azulejo em Portugal tem sido largamente usado na decoração de imóveis através do revestimento de superfícies arquitetónicas. Essa integração associada à história do edifício ao longo dos séculos levou a que muitos dos conjuntos tenham chegado aos nossos dias em mau estado de conservação. A degradação é manifestada pela perda de vidrado e os sais solúveis, em particular o cloreto de sódio, têm sido apontados pelos profissionais de conservação e restauro como responsáveis pelo seu destacamento. Porém nem sempre são visíveis eflorescências nos casos de destacamento do vidrado em que o material cerâmico fica exposto, nem se reconhece o típico resultado da arenização ou esfoliação do material cerâmico. Não é corrente a realização de análises laboratoriais preliminares às intervenções de conservação e restauro de azulejos. As análises, quando realizadas, baseiam-se na observação macroscópica da precipitação do sal dissolvido em água, por reação pela adição de reagentes específicos, ou na leitura de condutividade em processo de dessalinização, processos que não permitem a identificação de todas as espécies presentes. Este estudo teve como objetivo o levantamento das formas de degradação in situ, reconhecendo a presença (ou não) de sais solúveis a elas associados e determinando analiticamente a sua natureza. Pretendia-se também identificar potenciais correlações entre certos sais e determinadas formas de degradação. Inspecionaram-se 29 imóveis distribuídos pelo território continental português de Norte a Sul, 14 no interior e 15 junto ao litoral, com azulejos de produção de Lisboa e de Coimbra. Analisaram-se amostras de sal e pequenos fragmentos de chacota desagregada colhidos em obra, utilizando o microscópio electrónico de varrimento HITACHI 3700N com unidade de microanálise associada (SEM-EDS) do Laboratório HERCULES da Universidade de Évora. Como era expectável, nos imóveis na zona costeira o sal predominantemente encontrado foi o cloreto de sódio. Contudo, também se encontrou carbonato de sódio em grandes quantidades (trona). Nas zonas do interior predominam os sulfatos de cálcio e magnésio. O sulfato de cálcio foi o sal que registou o maior número de ocorrências. Foram também identificados cinco casos (três de interior e dois de exterior) com perda de vidrado que apresentavam chacota lisa e em cujas análises não foi detetada a presença de sais solúveis. Estes resultados comprovam que não é necessária a cristalização de sais solúveis para que haja perda da camada vítrea. Por outro lado, a presença de sais pode ser circunstancial ou atuar como factor de degradação oportunista, quando outras causas propiciam o aparecimento de superfícies de evaporação.

The consolidation treatment of azulejos is indispensable when there is a debilitated or disaggregated ceramic biscuit and/or one wishes to reestablish a weakened glaze-ceramic adherence. In this communication the impregnation profiles obtained via mass consolidation on ceramics conservation are presented. An acrylic resin, an ethyl silicate and a nanolime were used to determine the micro-drilling relevance for the evaluation of consolidation treatments applied on ceramics. This technique allowed to observe the impregnation patterns which cannot be determined by the mechanical strength tests (flexural and compression) commonly used to evaluate the consolidation effect.

No âmbito da atividade de investigação, o LNEC estabeleceu cinco eixos programáticos e elegeu os Recursos Naturais como um dos eixos estruturantes da Estratégia de Investigação e Inovação (2013-2020) visando, entre outros temas, o desenvolvimento de estudos relativos à valorização de resíduos e subprodutos industriais. Nesta comunicação é apresentada a estratégia do LNEC visando contribuir para a meta de 70% de valorização de RCD em 2020, a qual se centra em duas linhas de ação: suporte técnico e divulgação e comunicação.

Resumo: Um trabalho exploratório realizado pelo LNEC em 2012 mostrou que o recozimento dos azulejos era tecnicamente viável como opção de restauro. Esse trabalho conduziu a um projecto de investigação sobre o restauro dos azulejos de fachada e foi o tema de uma dissertação de mestrado apresentada à Universidade de Bolonha. O recozimento de azulejos de fachada enquanto alternativa à sua alienação (Figura 1) não parece dever suscitar dúvidas de princípio. No entanto a simples perspectiva de se reabrir o processo tecnológico de fabricação em alto fogo conduz a argumentações metodológicas que não têm paralelo no caso dos restauros a frio. Esta comunicação aborda a questão do recozimento dos azulejos à luz da abordagem teórica ao restauro, mostrando que o processo não pode ser afastado com base em princípios sem se considerar especificamente os casos em apreço e os ganhos expectáveis. Palavras-chave: restauro de azulejos; recozimento de azulejos; Teoria do Restauro. Abstract LNEC found, as a by-product of another research, that in at least some cases, azulejos could be restored by re-firing. That finding lead to a research project and an MSc dissertation presented to the University of Bologna. The re-firing of façade glazed tiles as a viable alternative to their outright dumping (Figure 1) should, in principle, present no doubts. However the mere idea of restoring in the kiln brings forth methodologic arguments unparalleled in other fields. The present communication discusses the re-firing of azulejos based on theoretical principles, aiming to demonstrate that it cannot be discarded straightforward without considering individually its advantages and possible applications.

A few years ago I supervised an MSc dissertation on the blue cobalt pigment in Portuguese glazed tiles (azulejos). Looking for sources on the history of the cobalt pigment in Europe, I was directed to two papers published in German and one (unpublished) in Dutch. Those were: Beiträge zur Geschichte der Kobaltfarbe und ihre Verwendung in der Keramik (Contributions to the history of the cobalt colour and its use in ceramics) by Josef Horschik, an article originally published in Keramos nr. 85, pp. 119-142, 1979; Das Sächsische Blaufarbenwesen und der Handel mit Kobaltfarben – nach Unterlagen der Bücherei der Bergakademie Freiberg (The Saxony blue pigment and the trade in the cobalt colour - according to documents in the library of the Bergakademie of Freiberg) by Peter Hammer, a communication to the VII Int. Symp. ‘Cultural Heritage in Geosciences’. Scripta Geol. Spec. Issue 4, Winkler Prins & Donovan, 2004; and Zaans Blauw - van zaffer tot smalt naar ultramarijn (Zaan Blue - from zaffre to smalt to ultramarine) by Martin E. de Gruijl (written after 1993 and presumed unpublished). I translated the relevant parts of the papers for the benefice of the student and, finding in them information that was new to me, kept in mind that I would one day write down an abstract of the contents that might help other researchers to source historic and technical information on the pigment so famously used in Portuguese azulejos. The present text includes selected information abridged from those valuable texts to tell the whole story with incompatibilities between two of them critically assessed and edited, complemented with other information to encompass the relevant period for the pre-industrial production of azulejos in Portugal. A number of personal comments are added, particularly in the conclusive chapter.

In documents from the 16th and 17th centuries we can read sometimes the expression “golden azulejos”. This is a matter that azulejo historians never fully studied but which raises interesting questions. Sometimes this expression could be related to azulejos in the “lusterware” technique, a secretive and complex process which allowed the ceramic surfaces to be decorated with gold and copper metallic shine. Another possibility to interpret the expression “golden azulejos” is related with a form of decoration used from the late 16th to the early 17th centuries. Sometimes the glazed surface of azulejos was painted with an oil-based golden paint, presumably over white tiles or over compositions of “enxaquetado” (chequered compositions) of several colours. Examples of these decorations are rare today due to the fraility of the process. With this presentation we aim to present two processes of decorations of azulejos in Portugal that remain almost ignored but in their time could return a quite staggering effect.

O revestimento epoxídico aplicado no interior das paredes de betão armado de uma câmara de ozonização apresentou sinais de degradação passados cinco anos da entrada em serviço. Dada a exposição contínua a água branda com ozono dissolvido, à ação da pressão hidrostática causada pela própria massa de água e à erosão provocada pela velocidade a que se movimenta a água na câmara, o betão armado foi revestido com um esquema de pintura de natureza epoxídica. Com vista ao diagnóstico da causa da degradação do revestimento, foi analisada toda a informação técnica disponível, foi realizada uma inspeção para efeitos de levantamento e avaliação da condição física desta infraestrutura (Inspeção Principal) e, posteriormente, foram recolhidas amostras para análise e ensaio em laboratório (Inspeção Detalhada). Com base nos resultados do estudo realizado, da informação recolhida na bibliografia específica e na normalização aplicável, foram identificadas as causas da patologia observada e recomendados sistemas de proteção do betão compatíveis com as condições no interior da câmara que poderão vir a ser utilizados neste tipo de aplicações, considerando o tempo de vida útil pretendido e a durabilidade dos materiais aplicados.

Few forms of artistic expression capture the nature and the way of life of the Portuguese as the azulejo does. Manufactured and used in other countries, sometimes with superior technical quality, some aspects, however, impart to the way it was and still is used in Portugal an unparalleled originality since the first batches, imported from Andalusia in the late fifteenth century, to the present day when it is used to line the public spaces of modern towns. This continued use is, in itself, a distinguishing aspect when compared to other European cases; however it is its capacity of renewal according to the needs of a given epoch that mostly marks the difference. The changes in taste, fashions, aesthetic expressions, or new requirements have found in the azulejo a flexible support, adaptable to new duties, adjustable to evolving social needs, but also shaping up to its different clienteles. With designs of lesser or greater erudition, both religious and profane, narrating mythological or historic facts with equal propensity, portraying everyday life or simply adjusting to the expressions of other arts, such as textiles, wood carving or metalwork, the Portuguese azulejo always “found” ways to adjust to new times and new ways and this aspect, allied to its natural duration as a finishing was a winning trump card. For all these reasons, the Portuguese General Directorate for Cultural Heritage intends to proceed with the candidacy to UNESCO in 2018 for the classification of architecturally integrated Portuguese azulejos as World Heritage. The preparations for this application began in 2009 with the partnership that the Museu Nacional do Azulejo (MNAz) established with the Laboratório Nacional de Engenharia Civil (LNEC). Following that partnership, teams were formed involving researchers from both organizations, and research projects have been carried out: on specific aspects related to the manufacture of azulejos; to determine causes and mechanisms so far unknown of their decay; and to verify analytically assumptions related to their history. The corpus of results will allow a better understanding of the azulejo and, hopefully, a much more effective approach to the conservation of architecturally integrated panels, ensuring that this most Portuguese of material cultural heritages will endure to be transmitted to future generations.

The use of Construction and Demolition Recycled Materials in sub-base layers of road pavements is analysed from an environmental perspective based on the results of leaching tests.

Semi-industrial glazed ceramic tiles lining urban façades represent a rich heritage asset of Portuguese cities and in particular of Lisbon. However, still a sizeable part of them is being continuously lost. Whenever the façade tiles are decayed, they are usually merely removed and replaced by newly manufactured ones. Following preliminary tests done at LNEC in 2012, we introduce in this communication re-firing as an alternative to simple disposal of damaged original tiles. We assess the technique as a technological option for the restoration of crazed and spalled tiles. The re-firings are applied at different heatworks and temperatures and the effects of all tests are studied by visual, microscopic observation and through the glaze resistance to a pull-off. The effect of continuous serviceability of the re-fired tiles is assessed through accelerated ageing tests. The domain of application of the technique and the shortcomings detected are presented and discussed in this communication. Dwelling on a new ground, we present the initial results on which further research in this field can be based.

This e-book and correspondent platform MyC3Place present the collection of the outcomes carried out by the partners of the C3Places Project. It explores the new dynamics of open spaces as a trusted service for community and expands our understanding on how mediated public open spaces function, paying attention to stakeholders, local context and different social groups. The e-book shows how it's possible to increase the quality of public open spaces (squares, parks, green spaces) as a community’s service, reflecting through ICT the needs of different social groups. Public spaces are critical for cultural identity, as they offer the place for interactions among generations and ethnicities. Even in the digital era, people still need contact with nature and other people to develop different life skills, values and attitudes, to be healthy, satisfied and environmentally responsible. Using ICT and co-creating with users, this e-book expands our knowledge on meeting emerging citizens’ needs about the future public space. All the contents are classified by means of keywords that are described on the following pages. Then the work of each partner is presented in detail.

C3Places - using ICT for Co-Creation of inclusive public Places is a project funded under the scheme of the ERA-NET Cofund Smart Urban Futures / Call joint research programme (ENSUF), JPI Urban Europe, https://jpi-urbaneurope.eu/project/c3places. C3Places aims at increasing the quality of public open spaces (e.g. squares, parks, green spaces) as community service, reflecting the needs of different social groups through ICTs. The notion of C3Places is based on the understanding that public open spaces have many different forms and features, and collectively add crucial value to the experience and liveability of urban areas. Understanding public open spaces can be done from a variety of perspectives. For simplicity’s sake, and because it best captures what people care most about, C3Places considers the “public” dimension to be a crucial feature of an urban space. Public spaces are critical for cultural identity, as they offer places for interactions among generations and ethnicities. Even in the digital era, people still need contact with nature and other people to develop different life skills, values and attitudes, to be healthy, satisfied and environmentally responsible. The book aims to spark discussion on the co-creation of public open spaces through the active involvement of different stakeholders in the production of a more inclusive, attractive and responsive urban environment. It intends to help researchers, governments and drivers in understanding and implementing more collaborative actions. The authors share experiences, visions and reflections on how co-creation and participatory processes can open up possibilities for a sustainable and equitable future. This book emphasises three dimensions: practice, reflection, and learning. Practice concerns driving actions, identified and analysed experiences that serve as key models. Reflection refers to exploring and examining the results and performances of a co-creation process. Co-creation is not the search for a final product, but rather a process and a new path to more responsive and inclusive communities. Learning refers to the knowledge transfer and replication induced by the synergy of the different actors involved in this book. The chapters which constitute this work were completed prior to Spring 2020, so the research and insights do not reference the global public health crisis caused by Covid-19. However, in such challenging times the argument for co-creation approaches to increase the potential of public spaces to support a range of inclusiveness outcomes is even stronger. This publication is based upon work of C3Places Project. The C3Places Project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 693443 and from FCT (Portuguese Funding Agency for Science, Research and Technology).

This volume aims to promote discussion and critical thinking on the urban environment at the intersection of the neighbourhood and the city, along their socio-spatial relations, from an interdisciplinary, multidimensional and international perspective. The chapters cover various aspects related to the meaning of living, intervening, planning, managing, thinking about and producing the city in the digital era, with a view to increasing the understanding of neighbourhoods as part of a wider consideration of social and sustainable development and the need for greater care of urban communities. This has a direct impact on public open spaces, which lie at the core of CyberParks. The international scope of the edition is enhanced by its bilingual nature, as this volume targets, in addition to a European readership, also the readership of Portuguese-speaking countries. This publication is based upon work from COST Action TU1306, supported by COST (European Cooperation in Science and Technology).

Vários

Publicação que regista os resumos expandidos realizados no âmbito do Congresso Ibero-americano "Património, suas matérias e imatérias", realizado nos dias 2-3 de novembro de 2016 no LNEC, contendo ainda em CDrom, os artigos completos.

Em 2011 cumpriram-se 100 anos sobre a publicação da Lei de Reorganização dos Serviços Artísticos e Arqueológicos da 1ª República (Maio de 1911). Este diploma constituiu uma referência incontornável no enquadramento do conceito de património que iria influenciar toda a prática da sua salvaguarda em Portugal. Por coincidência, cumpriram-se também neste ano os 80 anos da Carta de Atenas (Outubro de 1931), um marco histórico na produção de documentos orientadores de cariz internacional, que veio incentivar a produção de novas cartas e outros documentos internacionais que, em larga medida, ainda definem e sustentam as actuais práticas de preservação do património. O Instituto de História da Arte da Universidade de Lisboa e o Laboratório Nacional de Engenharia Civil quiseram com este simpósio assinalar aquelas efemérides oferecendo às comunidades científicas e profissionais uma oportunidade de reflectirem sobre estes acontecimentos pioneiros e debaterem as consequências que eles tiveram no período transcorrido desde então, como forma de compreender melhor a salvaguarda do património nos dias de hoje, perante os desafios e exigências da sociedade moderna. Os artigos recebidos, e que constam nas presentes actas, demonstram o interesse que o tema suscita e confirmam que o País está bem apetrechado para cuidar do seu património em todas as vertentes que tal objectivo exige. Ao juntarmos as valências de duas instituições tão diferenciadas, procurámos mostrar que a preservação é um conceito multifacetado, que necessita de contributos diversos, mas precisos, e que não pode ser abordado de forma unilateral ou voluntarista por um qualquer grupo profissional ou ditado por meios burocráticos como medida normalizada ou normalizável. Os trabalhos agora publicados dão conta dos primórdios das preocupações sobre preservação, discutem problemáticas que percorreram o Séc. XX e reflectem sobre as situações actuais, cumprindo cabalmente as nossas expectativas e enriquecendo o acervo de exemplos e de doutrinas que nos permitem afirmar que não é por falta de conhecimento, de experiências ou de competências realizadoras que ainda hoje vemos acontecerem intervenções desqualificadas, mal preparadas e desajustadas. As presentes actas aí estão para demonstrar que fazer mal ou abandonar património não têm que ser fatalidades de um país.

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In the construction sector, overall policies on resource efficiency and the circular economy have as one of their objectives the shift from the use of natural mate-rials to industrial by-products and materials recovered from waste. In this context, the assessment of the presence of hazardous substances in construction products and the corresponding implications for the environment

The Lisbon Living Lab will be centred on teenagers (young people 13 to 17 years of age) as they are a particular age group with specific needs and interests on public spaces, the relationship between teens and public spaces is very intrinsic, as public spaces may serve as a fundamental (play)ground for teenagers’ development. The Lisbon’s Alvalade neighbourhood will be living lab to explore how teenagers use and behaviour in urban fabric and what are they needs and preferences on public open spaces. The main objective is to engage teenagers in a process of the co-creation of urban spaces, by exploring the leading research question: “How can we capitalise on teenagers’ new-found love of the wired life (Thomas, 2013) to encourage them to be more outdoors?”

This chapter explores the potential of co-creation for the planning of public open spaces that could be more attentive to different, unequal and diverse social ideas, needs and desires. Co-creation is discussed as an innovative opportunity for learning and (re)thinking urban planning. Exploring ideas, literature and experiences (from the European Project C3Places), the chapter discusses the role of co-creation for involving citizens in placemaking. This reflection addresses co-creation as a collective, contextual and engaged process of learning. From this perspective, co-creation is discussed as an open process of learning about predictable ideas in the relationship between socio-spatial imaginary, requirements, needs and urban design procedures from a transformative perspective.

Public open space is a subject that belongs to us all. Every time we leave our homes, our private territory, we enter a space we have to share with others. Public space is the place for social interactions, strengthening sociability and ultimately exercising democracy. As a subject of study, public space has also long been analysed, explored and researched in various ways and under different guises, by planners, landscape architects and designers, anthropologists, social and cultural geographers, and urban historians. They all bring evidence on the role of public space in urban life, in the quality of urban environment and in the construction of cultural identity. Consequently, public space should deserve serious consideration by all - starting with those in charge and who hold regulatory responsibilities for those who use the places and ultimately give them life. As the UN-Habitat (2015) rightly recognises, a public space represents a key resource for social cohesion, economic development, and in particular liveability in urban settings. Public space is a resource that critically affects community values and positively impacts the quality of urban life. Backed by these premises, this book is about the co-creation of public open spaces, an issue at the core of the C3Places Project. To better understand the process, particularly the values of engaging people in the production of public space, is one of the C3Places’ objectives. The project is developing strategies and tools to help increase the quality and responsiveness of public spaces. In this process, the Project also aims to better understand how Information and Communication Technologies (ICTs) can influence co-creation and social cohesion. The chapters of this book bring science a little closer to the knowledge about the design, production and management of public spaces. 37 authors responded to the Project’s call to share experiences, visions and reflections on how co-creation and participatory processes can create possibilities for a sustainable and equitable future.

Face à metamorfose que se presencia na região da Avenida Almirante Reis, este capítulo discute a sua correlação com a criação de um novo discurso sobre a diversidade sociocultural. A partir do apelo a determinadas expressões — por exemplo, mundo e mundos — para enunciar a diversidade local, sugere-se a crescente transfiguração do discurso e a conexão com a economia cultural amplamente estimulada pela intervenção ali protagonizada. No desenvolvimento desta reflexão, privilegia-se o discurso produzido pela comunicação social.

The chapter considers the link between urban transformations in the Mouraria neighbourhood in Lisbon and the digital environment.The guiding thread of reflection is based on the tension between the production of sociocultural symbolic local references, and their (dis)appropriation by a creative economy that, relying on digital as a resource, helps to reshape the sociocultural local world into marketing. It concludes that digital has, not only a tangible social dimension, but also a tangible dimension in the processes of urban transformation. As such, it is pertinent to create alternative ways in defence of the right to the city that economize the social and its imageries taking more advantage of the articulated combination between real-digital.

This chapter is concerned with how digital technologies are changing habits, expectations and motivations in the use of public open spaces. These digital developments are a societal challenge with reflections on social practices and, on planning and design approaches to public spaces. This might also challenge the future development of information and communication technologies (ICTs). The discussion in this Chapter is based on knowledge and experience exchanges carried out within the COST Action CyberParks. The leading issue of CyberParks is how to use ICTs to transform our cities into more human environments, rather than just more high-tech places, and to understand that “smartness” should be people friendly. Through the structure of the project, the importance of comprehensive and trans-disciplinary development is introduced and justified. A theoretical approach and frameworks from ethnographic and technological perspectives that help us to better understand (potential) interactions are being developed, and both are at the centre of this discussion.

The aim of this chapter is to discuss the production of mediated public open spaces by investigating the impact of ICTs in a participation process, and from this discussion to develop arguments to base a theory on co-creating a cyberpark. It focuses on how digital interconnectivity, through its potential for engaging potential users, gives rise to new forms of agency in the design of public spaces.The conceptual framework is backed by the COST-Action Cyberparks, and the Project Flussbad, both tackle the reflection of the proliferation of ICT-related media in public open spaces.

This chapter discusses the act of walking as a method of capturing the socio-spatial needs of users in a contemporary urban space. Walking as method is considered a way to assimilate a socio-spatial proximity experience, and to (re)invent the response to urban space needs in a fast-changing city. This reflection discusses the purposes of urban planning, provides a framework, which goes from socio-spatial urban needs to (possible) responses, and discusses the complexity of evaluating the information gathered. It highlights the role of walking in planning, but also the relationship between plan and walk, discussing some of the key aspects to bear in mind when taking the act of walking as a way to learn how to plan. From the sensitive act of walking to the rational processes of collecting information, e.g., techniques for basic information collection for urban planning, this chapter also presents the role that ICT can play as an instrument of socio-spatial design in capturing relevant information for urban planning professionals.

The chapter discusses how ICT can be used to enhance the understanding of the relationship between space, users and social practices. As an example of possible use of ICT for capturing and better understanding user’s needs, the new digital tool WAY Cyberparks is presented and discussed. A “cyberpark” is defined as a new type of urban landscape where nature and ICTs blend together to generate hybrid experiences and enhance quality of life. The WAY Cyberparks digital tool consists of a smart phone application, server/cloud and web services. Through the experiences from testing it in selected urban open spaces in Barcelona, Lisbon and Ljubljana opportunities are presented and lessons are drawn about relevant aspects of the ICT towards building a more participatory and collaborative process in planning of public spaces. A relevant aspect of the ICT lays in their ability to enhance communication with (potential) users, transforming the production of public open spaces into an interactive process, and enabling creative community participation and empowerment. Furthermore, some challenges of the increasing penetration of digital technologies devices (smart phones, smart watches, tablets, etc.) within the broader context of their use in public urban open spaces such as parks, gardens, squares, plazas are discussed, together with the consequences of this interweaving, which is growing at a rapid pace, unfolds research needs in the future.

Atualmente existe grande interesse pelas técnicas construtivas com terra crua, que tinham caído em desuso mas que ressurgiram com a conscencialização face à ecoeficiencia e no sentido de explorar recursos locais reutilizáveis. A taipa é, a nível mundial, uma das mais antigas e difundidas técnicas de construção. Em Portugal a taipa reune grande atenção porque é uma das principais técnicas utilizadas na nova construção com terra. Mas esta atenção decorre também da necessidade de reabilitação de edifícios antigos e da existência de um vasto e valioso património arquitetónico, que precisa ser preservado. Muitos dos edifícios antigos de terra deterioraram-se por falta (ou ineficiência) de manutenção e reparação. De fato, existe um elevado desconhecimento ao nível das técnicas de reabilitação e conservação. O presente trabalho de investigação explora a questão da adequabilidade de argamassas para a reparação de paredes de taipa. A escassa informação nesta área justificou o estudo das caraterísticas mais adequadas para estas argamassas de reparação e definição de recomendações para sua aplicação. Partiu-se do pressuposto que, para perspetivar intervenções de reparação com maior ciclo de vida, é importante asseverar não só a durabilidade das argamassas de reparação, mas também a sua compatibilidade com a parede. A principal conclusão é que, sempre que possível, as argamassas devem ser efetuadas com a mesma terra utilizada na parede ou com materiais tão semelhantes a esses quanto possível, para que as propriedades físicas, mecânicas e químicas sejam compatíveis com as da parede a reparar. Se a taipa não tiver sido estabilizada com ligantes minerais, estes não devem também ser utilizados nas argamassas de reparação. Observou-se ainda que as argamassas estabilizadas com ligantes minerais apresentam uma absorção capilar muito mais rápida do que o mesmo tipo de argamassas sem estabilização e que a utilização de fibras vegetais potencia o aparecimento de bolores, quando as argamassas se encontram em ambientes com elevadas humidade relativa.

This thesis was aimed at understanding the behaviour of plasters and renders on salt-loaded walls. The current state-of-the-art and state-of-the-practice were accessed focusing particularly on old plastered/rendered buildings and their conservation practice in Portugal. Afterwards, experimental work was carried out aiming at answering the identified questions. Two laboratory techniques, for relative humidity control with salt solutions and for salt content determination by hygroscopic moisture content measurements, were investigated. Drying of salt-loaded materials was studied by means of drying experiments monitored using a magnetic resonance imaging (MRI) technique. The behaviour of plasters and renders in relation to salt crystallization was then accessed by means of crystallization tests and MRI-monitored drying tests. Most drying and crystallization tests were carried out on specimens composed by a plaster or render applied on a given substrate. Finally, the study of five old buildings in Portugal provided an insight into practice-related salt decay features. On the basis of this research, guidelines are proposed to select plasters and renders for salt loaded walls. Conclusions were also achieved on: (i) possibilities and limitations of the test methods, particularly salt crystallization tests, and diagnostic methodology used; (ii) salt decay processes, namely, influence of soluble salts on drying, mechanisms of salt-induced dampness and salt distribution in masonry; (iii) reasons for sodium chloride being typically much less damaging than sodium sulfate in laboratory tests; (iv) influence of factors such as the type of salt, kind of substrate material or presence of a paint layer on the behaviour of plasters and renders; (v) factors that can account for a worsening of salt damage after restoration interventions; (vi) field or application conditions that favour salt damage.

A ação dos sais solúveis e humidade nos edifícios antigos é uma causa frequente da sua degradação. Pretende-se com este trabalho estudar experimentalmente, através de ensaios laboratoriais, de que forma diferentes tipos de sais dissolvidos em água influenciam a absorção por capilaridade em materiais porosos. O levantamento do estado da arte incidiu sobre a ação de degradação dos sais solúveis sobre os materiais porosos, sobre as características dos materiais porosos e foca também os mecanismos de transporte da água, no estado liquido e de vapor, envolvidos nos processos de absorção capilar e secagem. A campanha experimental realizada incluiu o ensaio de absorção por capilaridade e o ensaio de secagem. Os materiais porosos utilizados foram o tijolo e a argamassa e utilizaram-se seis soluções salinas, de concentração saturada: cloreto de sódio, sulfato de sódio, cloreto de potássio, nitrato de sódio, nitrato de potássio e carbonato de sódio. Realizaram-se os mesmos ensaios com água, que serviram como referência. Esta dissertação permitiu tirar conclusões sobre: i) a influência dos sais na absorção por capilaridade; ii) processos de degradação, influência dos sais solúveis na secagem de materiais porosos; iii) a correlação existente entre a degradação dos materiais porosos com o tipo de sal.

Although Portuguese azulejos are such an important heritage asset, having been extensively studied from the Art Historian viewpoint, the knowledge concerning the raw materials used and the details of the technological manufacturing process is very limited. The research project behind this dissertation was aimed at improving the present knowledge as concerns the composition of the blue pigment used in the 17th and 18th centuries. A representative set of azulejos spanning at least 200 years from ca. 1600 to 1800 was selected and the composition of the blue colour in their glazes analysed. The results were assessed aiming to answer the following main questions: i- What are the characteristic compositions of the colour (pigment and impurities) and how do they relate with the chronology of the azulejos? ii- What are the compositional traits that bear on the shades of the blue colour? iii- Can Portuguese azulejos be separated from Dutch and Spanish productions, at times when they co-existed in Portugal, solely by the composition of the blue colour? iv- Is the composition of the blue colour related with provenance of azulejos within Portugal? v- Are there grounds to suspect that at some time the Portuguese used, besides the well-known German zaffre, alternative sources of blue colour imported through their wide sea trade routes?

The presence of moisture inside a material whose surface was treated with a water repellent agent may give rise to unwanted side-effects. Indeed, the temporal and spatial significance of moistening events may be intensified if a water-repellent, as any other kind of treatment, hinders drying. This effect can be particularly relevant for historical buildings, where moisture from varied origins is recurrently present in the masonry, but is also pertinent for more recent constructions since water often finds ways to penetrate the building elements, through cracks or joints. This article discusses the application of water repellent treatments on ceramic brick, with regard to drying of the masonry. The influence of cracks parallel or perpendicular to the surface is taken into account. Five silicone-based treatments were studied. The treated or untreated material was subjected to capillary absorption tests by which the effectiveness of the water repellent effect was estimated, as well as water vapour permeability tests and drying tests. The effectiveness of four out of the five treatments is high. Vapour permeability is not much affected in one case, when the cracks are parallel to the surface, and in none of the cases, when they are perpendicular. Nonetheless, drying is significantly delayed by any of the five products, both in the case where the cracks are parallel to the surface as when they are perpendicular.

A presente dissertação visa avaliar a eficácia de dois modificadores de cristalização com baixa toxicidade quando em aplicados em dois materiais porosos, contaminados com dois tipos de sal. Foram testados o ácido cítrico e o ácido fosfocítrico, aplicados por absorção capilar ou por pulverização, em provetes de argamassa de cal aérea ou pedra de Malta saturados com soluções salinas de cloreto de sódio ou sulfato de sódio a 10% (percentagem ponderal). Foi efectuada uma análise macroscópica do efeito dos dois modificadores, baseada em ensaios de secagem. A pesquisa do estado-da-arte incidiu sobre as características dos materiais porosos, transporte de água, sais solúveis e modificadores de cristalização. Na campanha experimental foram ainda realizados ensaios de caracterização da argamassa fresca, da argamassa endurecida e da pedra de Malta utilizadas. Determinaram-se também as características de porosidade, permeabilidade ao vapor de água, tensão superficial e evaporação das soluções, capilaridade e secagem. O trabalho realizado permitiu conhecer os principais desenvolvimentos recentes sobre modificadores de cristalização e concluir sobre a influência na secagem e a relevância dos dois modos de aplicação testados do ácido cítrico e do ácido fosfocítrico.

A acção dos sais solúveis é uma causa frequente de degradação dos edifícios antigos, reflectindo-se a vários níveis (e.g., estético, habitabilidade, segurança estrutural). Esta dissertação tem como objectivo efectuar a análise e sistematização de um leque abrangente de práticas actualmente utilizadas para controlo da degradação por sais solúveis. Neste âmbito, foi utilizada a análise documental de bibliografia posterior a 2000 e procedeu-se à análise crítica de métodos de controlo da degradação seleccionados: remoção mecânica de eflorescências; remoção de materiais contaminantes; compressas; remoção electroquímica de sais; microrganismos; modificadores de cristalização; rebocos; controlo ambiental; controlo da humidade ascensional; método do hidróxido de bário. Analisaram-se também algumas medidas práticas para prevenção do risco de ocorrência ou agravamento desta degradação. Adicionalmente, avaliou-se a complementaridade entre métodos, identificando eventuais benefícios de uma acção conjugada. A sistematização das práticas analisadas envolveu o seu enquadramento segundo três abordagens distintas: prevenção, correcção, e mitigação. A dissertação permitiu tirar conclusões sobre: (i) a actuação face à degradação provocada por sais solúveis, a qual deve pautar-se por uma compreensão global do problema; (ii) a importância das medidas preventivas, como meio para evitar os danos e custos associados; (iii) a relevância dos métodos de controlo da degradação, nas vertentes correctiva e de mitigação; (iv) a experiência actual sobre a utilização prática dos métodos em edifícios, designadamente com relação ao número de casos de estudo existentes; (v) a necessidade de uma boa compreensão das práticas referidas, nomeadamente em relação às vantagens e inconvenientes, a qual pode ser facilitada pela sua sistematização.

Estudou-se um conjunto de fragmentos de azulejos datados do século XVII, de produção portuguesa, cedido pelo Museu Nacional do Azulejo. O objectivo foi caracterizar morfológica e quimicamente a camada pictórica da azulejaria portuguesa do século XVII. O estudo utilizou uma abordagem multi-analítica, incluindo a espectrometria de fluorescência de raios X dispersiva de energias (µ-EDXRF), espectroscopia de Raman, o microscópio electrónico de varrimento com microanálise de raios X (SEM-EDS), e técnicas de observação incluindo o SEM e microscopia óptica. A azulejaria portuguesa do século XVII caracteriza-se por uma paleta cromática relativamente rica, que engloba o azul, amarelo, laranja, verde, púrpura, um tom púrpura acastanhado e ainda outro castanho muito escuro utilizado em contornos. As cores integram um fundo branco – o vidrado estanífero característico da majólica. Confirmou-se que o azul se deve ao óxido de cobalto, o púrpura ao óxido de manganês e um dos verdes, de aparência transparente, ao óxido de cobre. Os resultados indicam que o amarelo será uma variante do pigmento amarelo de Nápoles (antimoniato de chumbo), constituído por um óxido triplo de Pb-Sb-Zn. As outras cores são obtidas através de misturas: o laranja resulta da adição de hematite ao pigmento amarelo, o verde-seco resulta da adição de óxido de cobalto também ao pigmento amarelo, e os vários tons entre púrpura e castanho resultam da mistura de hematite com óxido de manganês em teores variáveis. Observaram-se morfologias distintas das cores: o amarelo, laranja e castanho-escuro permanecem à superfície do vidrado e conferem-lhe cores opacas. O azul, o verde-cobre e o púrpura difundem no vidrado em profundidade e, por vezes, horizontalmente. Os seus óxidos dissolvem-se na matriz vítrea, obtendo-se uma cor transparente. Com o verde-seco ocorre uma separação dos componentes da cor, na medida em que as partículas de pigmento amarelo permanecem à superfície, enquanto o azul difunde no vidrado.

A presente dissertação tem por finalidade compreender a influência dos tratamentos hidrófugos na secagem do tijolo cerâmico, tendo assentado na realização de ensaios de absorção capilar, permeabilidade ao vapor de água e secagem. Foi inicialmente avaliada a possibilidade de utilização de tijolo cerâmico maciço de três proveniências distintas. Uma destas origens foi a Praça de Touros do Campo Pequeno, em Lisboa, que permitiu estudar quatro tipos distintos de tijolo antigo. As outras duas origens foram as cerâmicas Torreense e de Vale de Gândara, tratando-se portanto neste caso de tijolos de fabrico recente. Os diferentes tipos de tijolo foram caracterizados quanto à sua aparência, morfologia, teor de sal, absorção capilar e comportamento em secagem. O tijolo de Vale de Gândara foi o tipo seleccionado para a aplicação dos tratamentos hidrófugos. Foi detectada a presença de fissuras neste tipo tijolo, tal como em todos os outros tipos caracterizados. Sendo este defeito relevante para o transporte de humidade, foi necessário ter em consideração a influência da orientação preferencial das fissuras. Assim, utilizaram-se em todos os ensaios provetes com fissuras paralelas e provetes com fissuras perpendiculares à superfície. Estudaram-se cinco tratamentos hidrófugos com base em silicone. Foram realizados ensaios de absorção capilar através da face tratada, ensaios de permeabilidade ao vapor de água e ensaios de secagem (método RILEM da curva de evaporação). Realizaram-se ensaios semelhantes sobre o material não-tratado, que serviram como referência. Os resultados do ensaio de absorção capilar indicam que a eficácia de quatro dos tratamentos é elevada, sendo a secagem do tijolo significativamente dificultada por esses quatro produtos. Verificou-se, no entanto, que o decréscimo da permeabilidade ao vapor apenas é significativo para três hidrófugos. A influência dos hidrófugos na permeabilidade ao vapor apenas é mensurável no caso dos provetes com fissuras paralelas à base. Quando as fissuras são perpendiculares à base, a permeabilidade ao vapor é bastante mais elevada, não sendo afectada pelo hidrófugo.

A presente dissertação visa compreender a influência dos revestimentos por pintura na secagem de materiais de construção porosos, tendo focado a nível experimental o caso dos substratos constituídos por uma argamassa de cal aérea. Aborda-se, em particular, o caso dos edifícios antigos e, mais especificamente, a situação das paredes com teor de humidade não desprezável que é muito corrente neste tipo de edifícios. O levantamento do estado-da-arte incide sobre as características dos materiais porosos, em particular as argamassas de cal aérea, e de diferentes tipos de revestimentos por pintura indicados para este tipo de utilização. Foca também os mecanismos de transporte de humidade envolvidos nos processos de secagem. Efectuou-se uma pesquisa de mercado e um inquérito ao meio técnico com o objectivo de perceber quais os revestimentos por pintura usados em intervenções de reabilitação / conservação e, assim, avaliar a situação da prática em Portugal. A campanha experimental a seguir realizada incluiu ensaios de permeabilidade ao vapor de água, de absorção capilar e de secagem e incidiu sobre dezasseis revestimentos por pintura disponíveis no mercado português. Treze destes revestimentos são tintas de silicatos, de silicone ou de pliolite que os respectivos fornecedores indicaram serem apropriadas para aplicação em paredes com problemas de humidade. Ensaiaram-se ainda duas tintas de cal de fabrico industrial e uma “tinta plástica” que serviu como referência. A dissertação permitiu obter dados sobre o estado-da-prática em Portugal, em particular no que se refere aos tipos de tintas usados em paredes de edifícios antigos com teor de humidade não desprezável. Permitiu também retirar conclusões sobre: (i) a influência dos revestimentos por pintura na secagem, na absorção de água por capilaridade e na permeabilidade ao vapor de água; (ii) a influência que o estado de humidificação do suporte pode ter no comportamento dos revestimentos; (iii) a correlação existente entre o comportamento à secagem (índice de secagem) e a permeabilidade ao vapor de água, que é a característica correntemente utilizada para prever o desempenho dos revestimentos.

A realização de auditorias pré-demolição a edifícios requer o envolvimento de várias partes interessadas, desde o proprietário, ao projetista e ao empreiteiro, com vista a maximizar a recuperação de materiais e elementos construtivos e minimizar a quantidade de resíduos de construção e demolição, de modo a impulsionar a economia circular no setor da construção. Estas auditorias devem ser realizadas antes do projeto de demolição ou reabilitação do edifício, de acordo com recomendações comuns. Para a realização dessas auditorias, foi desenvolvido este Guia Português para Auditorias Pré-Demolição e uma ferramenta em Excel com modelos padrão para a realização de um inventário aos recursos presentes no edifício. O inventário teve como base as orientações da União Europeia e do Quadro comum da União Europeia de Edifícios Sustentáveis

Os resíduos de construção e demolição (RCD) representam 46% do total de resíduos produzidos na Europa, cerca de 820 milhões de toneladas por ano, ou 5190 kg per capita. Vários constituintes dos RCD são potencialmente reutilizáveis e recicláveis, o que foca a atenção no seu papel relevante na promoção dos princípios da economia circular no setor da construção, na fase de fim de vida. Este enquadramento conceptual visa reunir as melhores práticas dos diferentes países relativamente à aplicação de auditorias de pré-demolição em edifícios como uma ferramenta útil para o desenvolvimento do guia português. É também abordada a necessidade de minimizar a geração de resíduos contaminados, durante a demolição ou reabilitação de edifícios, como um caminho relevante para maximizar a reutilização e reciclabilidade dos RCD e a qualidade dos materiais recuperados. Para este efeito, é apresentada uma lista de substâncias perigosas críticas e feita a identificação dos materiais de construção que potencialmente contêm constituintes perigosos. Neste relatório é descrita a atividade desenvolvida na tarefa T2

Foi fabricado um betão com agregados de minério de ferro proveniente de jazida de Moncorvo, para avaliação do potencial destes agregados para o fabrico de betão de elevada densidade. Com base nos resultados obtidos são feitas considerações sobre a densidade do betão que será possível obter em função da massa volúmica do agregado.

The research project DRYMASS – Drying of porous building materials possibly contaminated with soluble salts (PTDC/ECM/100553/2008) took place from February 2010 to January 2014. The project allowed advancing the knowledge on drying of porous building materials, as well as about how soluble salts and some types of surface layers affect that behaviour. A new method to characterize salt decay processes by optical profilometry was proposed, and the usefulness of NMR to clarify the causes of such processes demonstrated. There was also a provisional patent application, which was based on research results about the influence that lime coatings have on drying. The main findings of the project were specifically the following. Lime coatings may accelerate the drying of porous substrates. Also due to their high drying rate, ordinary building materials have a high evaporative cooling potential. With salt solutions, the drying kinetics of porous building materials is slower than with pure water. One of the causes is the reduction in sorptivity. Occasionally, there is also obstruction to vapour transport by the efflorescence. However, in most cases, porous efflorescence occurs, which pose no obstruction to this transport. Further, fissures or disaggregation may accelerate drying. Soluble salts amplify the effects that the natural heterogeneity of porous materials has on the drying kinetics. Due to the chaotic nature of the process, lime coatings will not necessarily enhance drying in this case. Sodium sulfate can be very destructive in the absence of high temperature or successive wet/dry cycles. A delamination pattern similar to those found in real constructions was observed on the well-known Ançã limestone. NMR showed that mirabilite and heptahydrate can both be responsible for this delamination pattern, in different conditions. Thermal expansion may be one of the mechanisms involved in salt decay processes.

In this report we describe an experimental study carried out at LNEC within the research project DRYMASS (ref. PTDC/ECM/100553/2008). The study was aimed at evaluating the possibility of increasing the drying rate of porous building materials by means of nano-treatments. It was justified by previous results of other authors that observed an apparently unexplainable increase in the evaporation rate of natural stone after application of nano-calcium hydroxide solutions as consolidating agents. Two commercial treatments, consisting on alcoholic or aqueous suspensions of nano-lime or nanosilica, respectively, were tested on three porous building materials. The treatments are generally used for consolidation. The materials were a lime mortar and two natural stones (Ançã limestone and Bentheimer sandstone). It was concluded that neither of the nano-treatments hinders drying. However, they were also not able to increase the drying kinetics of any of the three substrates.

The decay of porous building materials due to salt crystallization is very frequent and often significant in the built heritage and, thus, a proper understanding of the underlying processes has major importance for conservation. In this light, a new method for characterization of salt decay processes was developed within the DRYMASS research project, which is based on continuously measuring by optical profilometry the micrometric changes that occur on the material surface during drying. This method produces three different types of output: the so-called "alteration curve", as well as the current gravimetric evaporation curve and time-lapse photographs of the decay. But the three features had, until now, to be recorded using different specimens. This is an important limitation because the high uncertainty of salt decay processes may give rise to different decay patterns in similar specimens. Here, we present a development of the original study, which was afterwards carried out within the same project to allow evaluating the three features in a single specimen, by using an integrated set-up. This new study was carried out with two salts often found in salt decayed constructions, Na2SO4 and NaCl, and a material frequently used in the architectural heritage, Ançã limestone. Some of the experiments were performed after application of a water repellent treatment on the stone.

This is the third progress report of the research project "DRYMASS - Drying of porous materials possibly contaminated with soluble salts". It includes the following main sections: (i) A summary of the work, which briefly describes the activities undertaken in the reporting period and the results achieved, referring specifically to the tasks under execution in that period. (ii) A justification of the deviations from the Approved Proposal, both from a scientific or financial viewpoint. It also identifies the major difficulties in implementing the approved work plan, and how they will be overcome. (iii) A list of publications. It includes also the following annexes: Annex I – 2nd reformulation proposal with updated timeline; Annex II – Cryspom III - Book of abstracts and conference program; Annex III – Summary report on Cryspom III; Annexe IV – Figures and abstracts; Annexe V – Article submitted to Transport in Porous Media.

Conserving the built heritage today entails decisions and planning at several different levels. Firstly, analysis is necessary regarding what to conserve: values, authenticity and integrity are the key concepts at this macro level. Then, decisions on how to conserve them should consider the chief principles of good conservation practice, among which compatibility, retreatability and minimum intervention are prominent today. This report analyses these concepts and the different ways in which they were translated into the decision support systems that are nowadays resorted to, from values-based decision making and risk management in conservation to intervention planning and performance assessments. The ultimate goal of this analysis is to compile tools that promote a more rational decision making in conservation.

Este relatório sintetiza a atividade desenvolvida no LNEC visando contribuir para a aplicação dos materiais obtidos no processamento de resíduos de construção e demolição (RCD) no sector da construção, nomeadamente em betões e argamassas, em pavimentos rodoviários e em aterros e camadas de leito de infraestruturas de transporte. Esta atividade abrange as áreas de investigação programada, de investigação por contrato e outras atividades científicas e técnicas das quais se destaca a preparação de especificações técnicas específicas para estes materiais, a difusão de conhecimentos através da realização de ações de formação, da elaboração de documentos e da participação em conferências e outras reuniões científicas e técnicas. Nesta atividade integra-se também a cooperação com entidades, nacionais e estrangeiras, designadamente com universidades e associações de carácter científico e técnico. Sendo esta uma atividade transversal no LNEC O presente relatório integra o trabalho desenvolvido no Departamento de Materiais, no Departamento de Edifícios, no Departamento de Geotecnia e no Departamento de Transportes.

A empresa Repsol Polímeros, Lda, através de correio electrónico no dia 6 de Abril de 2011, solicitou ao Laboratório Nacional de Engenharia Civil (LNEC) a avaliação do estado de degradação de estruturas do Terminal Portuário do Porto de Sines, que incluíam dois viadutos localizados entre os postos de acostagem 4/5 e 9/10 da Área do Porto de Sines (APS)1 e o porto-cais do terminal de Graneis Líquidos2, e a apresentação de recomendações relativas à solução a adoptar para a recuperação das estruturas.

O Laboratório Nacional de Engenharia Civil tem vindo a desenvolver um estudo no domínio da conservação dos azulejos históricos que permitiu, nalguns casos relevantes, estabelecer uma ligação entre determinados defeitos de fabrico e formas específicas de degradação. Esse estudo demonstrou a conveniência no estabelecimento de um glossário ilustrado, incluindo defeitos de fabrico e formas de degradação e contemplando alguma terminologia nova. É esse trabalho, saído de uma colaboração com o Museu Nacional do Azulejo, que agora se apresenta num vocabulário que inclui também algumas definições básicas, cobrindo termos necessários às definições subsequentes de defeitos de fabrico e de formas de degradação. Os termos em relação aos quais pareceu aos autores poderem subsistir dúvidas têm anexas ilustrações exemplificativas.

Non-destructive or micro-destructive in situ tests are very relevant to the physical characterization of materials used in historical buildings. “Controlled penetration,” “sphere shock” and “sonic methods” can be used to evaluate the mechanical resistance of mortars and renders or to monitor the hardening process after their application. Used to evaluate surface hardness, micro-drilling (DRMS) is a very sensitive technique, and its use in this field is expected to contribute to more precise results. However, the diversity of the composition of mortars and the systematic presence of abrasive components are limiting factors for the use of this method in this field. In this study, several mortars with different composition and hardness are compared using drilling resistance as the comparative parameter. The mortars were applied on-site aiming at their use in real situations. Extracted mortar samples were tested in the laboratory using resistance drilling which was complemented by additional methods currently used for in situ characterization of these materials. The results highlight the need for an integrated perspective of laboratory and on-site information.

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