Papers
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Unstabilised Rammed Earth: Characterization of Material Collected from Old Constructions in South Portugal and Comparison to Normative Requirements
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.
Year: 2012
Number Pages:
25p.
Author(s): Gomes, I.; Gonçalves, T. D.; Faria Rodrigues, P.
: International Journal of Architectural Heritage
Editor: Taylor and Francis
Volume:
DOI:10.1080/15583058.2012.683133M.
Keywords: Normative documents; Requirements; Soil properties; Earth construction; Unstabilised rammed earth
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Water Vapor Emission From Rigid Mesoporous Materials during the Constant Drying Rate Period
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.
Year: 2012
Number Pages:
12.
Author(s): Gonçalves, T. D.; Brito, V.; Pel, L.
: Drying Technology
Editor: Taylor & Francis
Volume:
30.
Keywords: Porous media; Pore network; Heat and mass transfer; Drying rate; Constant drying rate period
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Chemical Shrinkage of Pastes Made with Shrinkage Reducing Admixtures
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.
Year: 2011
Number Pages:
pp 105-113.
Author(s): Ribeiro, A. C.
: Key Engineering Materials
Editor: Trans Tech Publications
Volume:
Vol. 466 (2011).
Keywords: Admixtures; Shrinkage
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Coatings applied on damp building substrates: performance and influence on moisture transport
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 paints 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.
Year: 2011
Number Pages:
513525.
Author(s): Brito, V.; Gonçalves, T. D.; Faria Rodrigues, P.
: Journal of Coatings Technology and Research
Editor: Springer
Volume:
8 (4).
Keywords: Moisture transport; Drying; Damp; Old building; Paint system
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Construction and demolition waste generation and management in Lisbon (Portugal)
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.
Year: 2011
Number Pages:
13.
Author(s): Braz de Melo, A.; Gonçalves, A.; Martins, I. M.
: Resources, Conservation and Recycling
Editor: Elsevier
Volume:
55 (12).
Keywords: Management; Generation; Demolition; Construction; Waste
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Evaluation of Adhesion Promotion Techniques for Structural 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 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.
Year: 2011
Number Pages:
331352.
Author(s): Custódio, J.; Broughton, J.; Cruz, H.
: The Journal of Adhesion
Editor: Taylor & Francis Group, LLC
Volume:
87(4).
Keywords: Surface treatments; Structural bonded joints; Solid timber; Durability; Adhesion promoters; Epoxy
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Rehabilitation of timber structures Preparation and environmental service condition effects on the bulk performance of epoxy adhesives
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.
Year: 2011
Number Pages:
3570-3582.
Author(s): Custódio, J.
: Construction and Building Materials
Editor: Elsevier, Ltd.
Volume:
25(8).
Keywords: Service conditions; Moisture; Preparation conditions; Epoxy adhesives; Durability
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A review of factors influencing the durability of structural bonded timber joints
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.
Year: 2009
Number Pages:
173-185pp.
Author(s): Custódio, J.
Editor: International Journal of Adhesion and Adhesives
Volume:
29/2.
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Activation of timber surfaces by flame and corona treatments to improve adhesion
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.
Year: 2009
Number Pages:
167-172pp.
Author(s): Custódio, J.; Broughton, J.; Cruz, H.; Winfield, P.
Editor: International Journal of Adhesion and Adhesives
Volume:
29/2.
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Assessment of characteristic compressive strength in structures by the rebound hammer test according to EN 13791: 2007
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.
Year: 2009
Number Pages:
249-254.
Author(s): Monteiro, A.; Gonçalves, A.
Editor: Laboratoire Central des Ponts et Chaussées
Keywords: Análise de regressão; Resistência do betão in situ; Esclerómetro; Intervalos de tolerância
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Comunicação
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16th century azulejos - what lies beneath the ground of Lisbon?
In the Vila Viçosa Palace, in the southern Portuguese province of Alentejo, lie the still impressive remains of what was the most extensive commission of azulejos produced in Antwerp for Portugal. Through an inventory made in 1563, after the death of the 5th Duke of Braganza D. Teodósio, it was found that no less than 3,658 azulejos commissioned to Antwerp had been delivered until that year. Until recently there was no known parallel between the pieces commissioned to Antwerp for the Palace of Vila Viçosa and other commissions for Portugal. With an excavation in Lisbon, in the area of the Escolas Gerais, five azulejos and two fragments, also of Flemish production, were found in what was probably a dump, because they were part of the frame of a panel of which nothing more was found. Other excavations in Lisbon, namely near Casa dos Bicos, Largo do Corpo Santo, Largo do Carmo, Palácio dos Condes de Penafiel and the grounds of the former Igreja de Santo André in Graça produced more more fragments of 16th century azulejos of varying provenance giving us a glimpse of an unexpected wealth of types and decorations used in the Lisbon of the 2nd half of the 16th century at a time when a local production of faience azulejos was just starting. Other pieces are now appearing in different archaeological contexts giving testimony of a maybe discrete but nevertheless assured trend that needs to be acknowledge. Their presence points to the spread of the appreciation for faience tiles and in these remains may well lie the foundations for the Portuguese taste for azulejos that lasts to this day. This communication reviews some of the findings supported by scanning electron microscopy observations and analyses trying an integration of some cases into known provenances or types.
Year: 2018
Number Pages:
298-312pp of the Book of Proceedings in digital su
Author(s): Pais, A.; Sequeira, M.; Monge, M.; Esteves, L.; Castanheira, I.; Valongo, A.; Manso, C.; Filipe, V.; Cardoso, A.; Mimoso, J.
: Proceedings of GlazeArt2018 (full articles on digital support)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Archaeological findings in Lisbon; Excavated majolica; Tiles from Antwerp; Renaissance majolica
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Adolescentes, tecnologias digitais e espaço público urbano: experiências com um Living Lab em Lisboa
Visa-se discutir a relação entre jovens, espaço público urbano e tecnologias de informação e comunicação (TIC), tendo por referência um estudo de caso em curso. O trabalho enquadra-se no Projeto Europeu C3Places, cujo objetivo é explorar os recursos digitais como apoio ao desenho de espaços públicos urbanos mais adequados às necessidades das pessoas. O estudo de caso em Lisboa assenta numa perspetiva de Living Lab onde se visa trabalhar ideias co-criadas com alunos da escola secundária com 3º ciclo Padre António Vieira, sita no bairro de Alvalade, em Lisboa. Tendo por referência a ligação dos adolescentes às TIC, é abordado um conjunto de iniciativas desenvolvidas a partir de oficinas temáticas de urbanismo, destacando-se uma aplicação móvel (app) desenvolvida como elo de comunicação entre adolescentes e os espaços.
Year: 2018
Number Pages:
174-180pp.
Author(s): Almeida, I.; Menezes, M.; Costa, C.; Batista, J.
Editor: Universidade de Coimbra
Keywords: Espaço Público Urbano; Living-lab; Adolescentes; Co-criação
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An unknown jigsaw in the Cathedral of Setúbal
A series of disperse renaissance azulejos with images in white with blue contours over a yellow background was recently uncovered, secluded by the basal wall of the altar of the Cathedral of Setúbal, near Lisbon. The azulejos were probably once part of a chapel lining that was removed and some were re-applied here at an unknown time. They were spread without any concern whatsoever about continuity, also because they were not intended for visibility. We attempted a partial digital reconstruction that allowed the perception of two feminine winged figures, together with flowers and fruits. One of the figures is an elderly woman with bird wings and the other a young lady with butterfly wings. Both have crowns, although of different sorts. The painting of motives in white with blue contours against a yellow background relates them graphically with the panels of the São Roque Chapel in Lisbon, but there are tantalizing differences. The Setúbal panels seem to bear testimony of a more archaic technology; the vertical placement of at least some azulejos in the kiln left remains of the supporting pieces and resulted in extensive drips that tarnished the composition. Another aspect is that the hand of the painter of Setúbal is amateurish compared to the proficiency of Francisco de Matos, the painter of São Roque. Yet, these azulejos can be highly important in establishing the evolution of the majolica technology in Portugal of which they may well be one of the earliest examples. This communication depicts a partial restitution of the painting, reports the first study made of the azulejos with instrumental support and discusses their technological placement towards other examples of known origin.
Year: 2018
Number Pages:
21-22pp in the Book of Extended Abstracts.
Author(s): Pais, A.; Rosmaninho, R.; Mimoso, J.; Esteves, L.; Cardoso, A.
: Proceedings of GlazeArt2018 (extended abstracts on printed book)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Sé de Setúbal; Igreja de Santa Maria de Setúbal; Portuguese azulejos; Renaissance majolica
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Analytical study of the azulejos from Igreja da Graça in Lisbon, signed by João de Góis
After the panels of Capela de São Roque in Lisbon, signed and dated, the incomplete and dispersed panels in Igreja da Graça are the second set of signed Renaissance azulejos produced in Lisbon that were found. A selection of azulejo units from the panels has now been studied by scanning-electron microscopy coupled with energy-dispersive spectrometry (SEM-EDS). The tiles making up the book bearing the signing monogram have been used to establish a morphological and analytical template aimed at identifying in the future a common officinal provenance in azulejos of the same general chronology known or presumed to have been produced in Lisbon. This communication reports the results of the analytical study identifying the main micro-morphological features and the composition variations.
Year: 2018
Number Pages:
13-14pp in the Book of Extended Abstracts.
Author(s): Mimoso, J.; Pais, A.; Esteves, L.; Silva, M.; Cardoso, A.; Antunes, M.; Morais Pereira, S.; Candeias, A.
: Proceedings of GlazeArt2018 (extended abstracts on printed book)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Early azulejo production in Portugal; João de Góis; Renaissance majolica
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Carbonation and environmental impact of concrete
The development of European standards intended to provide a framework for assessing the sustainability of construction works was by far the most important step towards the evaluation and comparison of their environmental, economic and social performance. From an environmental perspective, the use of Environmental Product Declarations (EPD) allows an informed choice of the more sustainable construction materials. The development of an EPD calls for specific guidelines that enable different manufacturers to evaluate equally the environmental impacts of their products during the different stages of their life cycle, i.e., the Product Category Rules (PCR). In the last years, the CEN/TC104/SC1/TG20, together with CEN/TC229/WG5, has made relevant progress on establishing PCR for concrete and precast concrete products leading to the publication of the European standard EN 16757 in June 2017, while a CEN Technical Report on CO2 uptake in concrete is about to be concluded. This paper, after presenting the general view of the normative approach for all the construction materials, makes a comprehensive analysis of the above documents, with particular focus on the relevance of carbonation on the environmental impact of concrete and concrete products
Year: 2018
Number Pages:
844-851pp.
Author(s): Martins, I. M.; Goncalves , A.
: Atas do Congresso BE2018
Editor: Grupo Português de Betão Estrutural (GPBE)
Keywords: Environmental impact; CO2 uptake; Carbonation; Concrete
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Influence of the production technology on the morphological characteristics of azulejos
In this article some aspects of the production technology connected with the preparation of the glaze and of the biscuit and with the firing cycle have been researched in order to better understand their effects on the morphological and chemical characteristics of the glaze and glaze-biscuit interface. Azulejo reproductions have been prepared by using raw and fired ceramic bodies glazed with either a lead-tin raw preparation or with a frit of different quartz grain sizes. The firing temperatures and the duration of the firing cycles have also been varied. The resulting cross-sections of the ceramic reproductions were analyzed with SEM-EDS. An increase in the Pb enriched K-feldspars formed at the glaze-biscuit interface is observed as the maximum temperature increases and the cooling rate slows. The use of raw glazes and single firings also promotes the growth. The results led to a better interpretation of the technological fingerprint observed on historic glazed tiles and offer more insight into the early azulejo production technologies and on the nature of the glaze-ceramic interface.
Year: 2018
Number Pages:
140-149pp of the Book of Proceedings in digital su
Author(s): Morais Pereira, S.; Antunes, M.; Cardoso, A.; Costa, M.; Delgado Rodrigues, J.; Esteves, L.; Mirão, J.; Candeias, A.; Mimoso, J.
: Proceedings of GlazeArt2018 (full articles on digital support)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Influence of technology in glaze morphology; Azulejo production technology; Azulejo interfaces; Majolica reproduction study
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On the use of glaze and ceramic body analytical spectra in heritage azulejos as beacons of provenance
During the past three years a research group including the Museu Nacional do Azulejo (Portuguese National Azulejo Museum), the Laboratório Nacional de Engenharia Civil and the HERCULES Laboratory of the University of Evora, acquired X-ray fluorescence spectra of the glazes of azulejo panels on site and single tiles from the collections of the Museum. That data was recently complemented by spectra obtained with the micro-analysis unit of a scanning electron microscope and with the AGLAE proton accelerator installed at the Carrousel du Louvre in Paris. By comparing spectra obtained on significative areas it is possible to obtain a glimpse of alikeness or of dissimilarity pointing to a similar or to a different officinal origin. This communication presents the method through a number of exemplificative cases.
Year: 2018
Number Pages:
439-450pp of the Book of Proceedings in digital su
Author(s): Mimoso, J.; Antunes, M.; Morais Pereira, S.; Candeias, A.; Pais, A.
: Proceedings of GlazeArt2018 (full articles on digital support)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Provenance studies; SEM-EDS spectra in archaeometry
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SEM-EDS research on mineral inclusions found in the biscuit of azulejos as a tool for provenance studies
During the year starting on July 2017, the Museu Nacional do Azulejo (Portuguese National Azulejo Museum), the Laboratório Nacional de Engenharia Civil and the HERCULES Laboratory of the University of Evora made a joint effort in the instrumental study of 16th century Portuguese azulejos, aimed at establishing their origin, technology used and eventual systematization of workshop productions. The microscopic observation of the biscuits did not reveal any signs of mixtures of clays, as are routinely perceived through the banded colours seen in the biscuits of 17th century Portuguese productions. Therefore, it seems likely that the workshops used plain marls with a suitable composition to grant compatibility of the biscuit with the glaze and thus their composition is a prime choice to confirm a local provenance. Azulejo samples are collected from panels on the walls and are necessarily superficial and very small. In such samples the biscuit composition as pertains to minor and trace elements is tainted by the penetration of the raw glaze and digestion phenomena over firing. However inclusions of minerals that are infusible at the kiln temperatures remain largely unaltered. A means to discriminate provenance based on a morphologic and compositional study of the small inclusions found in biscuit sections, often less than 5µm across, is proposed in this communication. These include mineral inclusions, both with and without repetitive morphologies, and micro-fossils. This communication reviews the inclusions repetitively found in Portuguese 16th century azulejos as a first step for the construction of a database aimed at exploring their potential as provenance markers.
Year: 2018
Number Pages:
393-409pp of the Book of Proceedings in digital su
Author(s): Mimoso, J.; Costa, D.; Antunes, M.; Cardoso, A.; Esteves, L.; Mirão, J.; Pais, A.
: Proceedings of GlazeArt2018 (full articles on digital support)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Use of SEM-EDS in the study of majolica; Azulejos; Mineral inclusions in ceramics; Provenance of ceramics
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Studies on azulejo glaze welding by means of laser irradiation
Azulejos (Portuguese glazed tiles) suffer from pathologies such as glaze fissures and glaze loss particularly as a result of exposure to wall moisture and weathering. Many tile panels need conservation measures, including the treatment of lacunae but there is currently a lack of efficient and long-lasting solutions. Lasers offer a number of unique advantages including for the study and conservation of cultural heritage. In the conservation/restoration field, up to now the attention of the scientific community has been focused mainly on the use of lasers for cleaning processes. In this communication the initial studies on a novel application of laser radiation for the controlled thermal fusion of a glaze are presented and its potential for the restoration of azulejos discussed. The influence of a CO2 laser processing parameters (focus distance, duration of the beam incidence, number of laser passes) have been tested in order to assess their effect on the test items. Tile replicas and authentic historic azulejo samples, of different glaze compositions and colours, have been irradiated. Optical and SEM microscopy have been used to study the morphological alterations and the impact on the laser irradiated glazes. Initial results are encouraging and further work towards the implementation of this methodology is in progress.
Year: 2018
Number Pages:
194-207pp of the Book of Proceedings in digital su
Author(s): Morais Pereira, S.; Hatzigiannakis, K.; Polychronak, E.; Melessanaki, K.; Pouli, P.; Mimoso, J.
: Proceedings of GlazeArt2018 (full articles on digital support)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Azulejos; Laser restoration of glazed ceramics
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Technical identification of the earliest productions of faience tiles in Lisbon
During the last year, the Museu Nacional do Azulejo (MNAz- Portuguese National Azulejo Museum), the Laboratório Nacional de Engenharia Civil (LNEC) and the HERCULES Laboratory of the University of Evora made a joint effort in the instrumental study of 16th century faience azulejos, aimed at identifying those of Portuguese origin based on their composition and the technology used and thus establish on firmer ground the origins of the production of faience azulejos in Lisbon towards a candidacy of Portuguese azulejos to the World Heritage List. This communication presents some of the first results.
Year: 2018
Number Pages:
11-12pp in the Book of Extended Abstracts.
Author(s): Mimoso, J.; Antunes, M.; Morais Pereira, S.; Esteves, L.; Cardoso, A.; Candeias, A.; Pais, A.
: Proceedings of GlazeArt2018 (extended abstracts on printed book)
Editor: Laboratório Nacional de Engenharia Civil
Keywords: Azulejos; Renaissance majolica
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Books
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C3Places - Using ICT for Co-Creation of Inclusive Public Places
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 communitys 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.
Year: 2021
Number Pages:
83.
Author(s): Costa, C.; Batista, J.; Almeida, I.; Menezes, M.
: Using ICT for Co-Creation of inclusive Public Spaces
Editor: Edições Universitárias Lusófonas
Keywords: co-creation; public spaces; ICT; C3Places
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Co-Creation of Public Open Places. Practice - Reflection - Learning
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 simplicitys 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 Unions Horizon 2020 research and innovation programme under grant agreement No 693443 and from FCT (Portuguese Funding Agency for Science, Research and Technology).
Year: 2020
Number Pages:
264p..
Author(s): Costa, C.; Ma?iulien?, M.; Menezes, M.; Marui?, B.
: Co-Creation of Public Open Places. Practice - Reflection - Learning
Editor: Edições Universitárias Lusófonas
Volume:
4.
Keywords: Cocreation; C3Places; Urban public space
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Neighbourhood & City - Between digital and analogue perspectives
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).
Year: 2019
Number Pages:
451p..
Author(s): Menezes, M.; Costa, C.
: Neighbourhood & City - Between digital and analogue perspectives
Editor: Edições Universitárias Lusófona
Volume:
3.
Keywords: City; Cyberparks; Analogue; Digital
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On the origin of majolica azulejos production in Portugal
Vários
Year: 2019
Number Pages:
138p.
Author(s): Pais, A.; Reis, M.; Campelo, J.; Mimoso, J.; Silva, M.; Morais Pereira, S.; Antunes, M.; Cardoso, A.; Esteves, L.; Candeias, A.; Filipe, V.; Matos, M.; Morna, T.; Simões, J.
: Estudos em Cerâmica Vidrada Patrimonial
Editor: LNEC
Keywords: PT; Physical-chemical characterization; Azulejo; Manufacture; Glazed ceramics; Historic heritage
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Livro de Resumos - Congresso Ibero-Americano "Património, suas matérias e imatérias
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.
Year: 2016
Number Pages:
366p.
Author(s): Menezes, M.; Delgado Rodrigues, J.; Costa, D.
Editor: LNEC
Keywords: Valor; Património imaterial; Património material; Reabilitação; Conservação do património; Participação social; Desenvolvimento sociocultural; Património cultural; Congresso Internacional
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Simpósio Património em Construção - Contextos para a sua preservação
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.
Year: 2011
Number Pages:
425pp.
Author(s): entidade LNEC
Editor: LNEC
Keywords: Congresso internacional; Conservação de património; Otecção do património; Património; Pt
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Avaliação, Conservação e Reforço de Estruturas de Madeira
N/A
Year: 2009
Author(s): Saporiti Machado, J.; Cruz, H.; Custódio, J.; Palma, P.; Dias, A.
Editor: Verlag Dashöfer
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Capítulo de Livro
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ICE manual of construction materials
N/A
Year: 2009
Author(s): Broughton, J; Custódio, J.
Editor: Thomas Telford Ltd
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Tese de Doutoramento
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Conservação de construções de taipa: argamassas de reparação.
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.
Year: 2013
Number Pages:
357p.
Author(s): Gomes, I.
Keywords: Argamassas de reparação; Taipa; Construção com terra; Terra
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Salt crystallization in plastered or rendered walls
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.
Year: 2007
Number Pages:
262.
Author(s): Gonçalves, T. D.
Keywords: Conservation; Built heritage; Cultural heritage; Renders; Plasters; Suflorescence; Efflorescence; Salt damp; Salt weathering; Salt decay; Crystallization; Salts; Efflorescencesoluble salts
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Dissertação de Mestrado
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Absorção por capilaridade de soluções salinas em materiais porosos
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.
Year: 2013
Number Pages:
90.
Author(s): Azevedo, J.
Keywords: Materiais porosos; Sais solúveis; Secagem; Absorção capilar
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The blue in Portuguese historical azulejos
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?
Year: 2012
Number Pages:
110.
Author(s): Fares, M.
Keywords: Majolica colours; Cobalt blue; Glazed ceramics; Azulejo
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Drying of red ceramic brick. Effect of five silicone-based water-repellent treatments.
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.
Year: 2011
Number Pages:
81-92.
Author(s): Couto, S.; Gonçalves, T. D.; Grandão Lopes, J.
Keywords: Drying; Surface treatment; Hydrophobic; Water-repellent; Ceramic brick
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Análise macroscópica do efeito de dois modificadores de cristalização com baixa toxicidade
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.
Year: 2010
Number Pages:
106p.
Author(s): Cardeira, A.
Keywords: Sulfato de sódio; Secagem; Sais solúveis; Modificadores de cristalização; Materiais porosos; Inibidores de cristalização; Cloreto de sódio; Ácido fosfocítrico; Ácido cítrico
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Controlo e reparação de anomalias devidas à presença de sais solúveis em edifícios antigos
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.
Year: 2010
Number Pages:
83p.
Author(s): Puim, P.
Keywords: Edifícios antigos; Reabilitação; Degradação; Prevenção; Sais solúveis
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Estudo da camada pictórica na azulejaria portuguesa do século XVII
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.
Year: 2010
Number Pages:
41.
Author(s): Coentro, S.
Keywords: Heritage tiles; Glazed ceramics; Cerâmica vidrada; Composição e morfologia da cor; Análise química; Azul de cobalto; Pigmentos; Azulejos históricos
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Utilização de hidrófugos de superfície em materiais cerâmicos. Influência na secagem.
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.
Year: 2010
Number Pages:
170.
Author(s): Couto, S.
Keywords: Edifícios antigos; Materiais porosos; Tratamentos superficiais; Humidade; Secagem; Tijolos; Materiais cerâmicos; Hidrófugos
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Influência dos revestimentos por pintura na secagem do suporte
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.
Year: 2009
Author(s): BRITO, Vânia
Keywords: Transporte de humidade; Argamassas de cal; Secagem; Materiais porosos; Edifícios antigos; Tintas de cal; Tintas de pliolite; Tintas de silicone; Tintas de silicato; Revestimentos por pintura
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Relatório Científico
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Guia Português para Auditorias Pré-Demolição
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
Year: 2023
Author(s): Vieira, M.; Rezvani, S.; Couto, P.; Salvado, A.; Falcão Silva, M. J.; Martins, I. M.
Keywords: Valorização; Resíduos de construção e demolição; Reciclagem; Reutilização; Economia circular; Auditorias pré-demolição; Guia
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Auditorias de pré-demolição - Enquadramento concetual
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
Year: 2022
Author(s): Rezvani, S.; Salvado, A.; Falcão Silva, M. J.; Martins, I. M.
Keywords: Gestão de recursos; Resíduos de construção e demolição; Valorização; Reciclagem; Reutilização; Economia circular; Auditorias de pré-demolição
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Betão de elevada densidade com agregados de minério de ferro de Moncorvo
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.
Year: 2017
Author(s): Ribeiro, A. C.
Keywords: Agregado de elevada densidade; Minério de ferro; Betão de elevada densidade
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DRYMASS Drying of porous building materials possibly contaminated with soluble salts (PTDC/ECM/100553/2008): Final Report
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.
Year: 2014
Number Pages:
35.
Author(s): Gonçalves, T. D.
Keywords: Final report; Fct; Research project; Soluble salts; Porous building materials; Drying
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Influence of nano-lime and nano-silica consolidants in the drying kinetics of three porous building materials
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.
Year: 2014
Number Pages:
24pp.
Author(s): Musacchi, J.; Gonçalves, T. D.
Editor: LNEC
Keywords: Porous materials; Drying; Nano sílica; Nano-lime
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The altertion kinetics curve and time-lapse imaging - Useful features in salt crystallization tests
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.
Year: 2014
Author(s): Musacchi, J.; Gonçalves, T. D.
Keywords: Time-lapse photography; Optical profilometry; Drying curve; Alteration curve; Crystallization tests; Drying; Crystallization; Soluble salts
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Report Year 3 of the Drymass research project
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.
Year: 2013
Number Pages:
143p.
Author(s): Gonçalves, T. D.
Editor: LNEC
Keywords: Drying; Soluble salts; Drymass project; Progress report
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Some conceptual tools for deciding and planning in built heritage conservation
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.
Year: 2013
Number Pages:
137pp.
Author(s): Revez, M. J.
Editor: LNEC
Info
Resíduos de construção e demolição - Atividade desenvolvida no LNEC
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.
Year: 2012
Number Pages:
35pp.
Author(s): Martins, I. M.; Veiga, M. R.; Roque, A. J.; Freire, A. C.; Batista, F. A.; Fortunato, E.
Editor: LNEC
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AVALIAÇÃO DA DEGRADAÇÃO DO BETÃO ARMADO DOS VIADUTOS ENTRE OS POSTOS DE ACOSTAGEM 4/5 E 9/10 DA APS
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.
Year: 2011
Number Pages:
46p.
Author(s): Ribeiro, M. S.; Monteiro, A.
Editor: Divisão de Divulgação Científica e Técnica - LNEC
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Vocabulário ilustrado da degradação dos azulejos históricos
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.
Year: 2011
Number Pages:
41pp.
Author(s): Mimoso, J.; Esteves, L.
Editor: LNEC
Keywords: Pt; Vocabulário técnico; Defeito de material de construção; Degradação de material de construção; Património histórico; Azulejo
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Outro
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Betões - Metodologias para prevenir reações químicas expansivas de origem interna
N/A
Year: 2022
Author(s): entidade LNEC
Keywords: Especificação; Betão; Expansão do betão; Reação sulfática interna; Reações alcalis-agregado
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Betões - Pozolanas especificações para uso no betão
N/A
Year: 2022
Author(s): entidade LNEC
Keywords: Especificação; Betão; Norma; Agregados; Pozolana
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Betões - Avaliação da conformidade do recobrimento das armaduras
N/A
Year: 2021
Author(s): entidade LNEC
Keywords: Especificação; Marca de conformidade; Inspeção; Betão; Recobrimento de armaduras
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Betões - Guia para a classificação de superfícies de betão à vista
N/A
Year: 2021
Author(s): entidade LNEC
Keywords: Especificação; Betão aparente; Betão armado; Superfícies de betão
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Planning Perspectives and Approaches for ActivatingUnderground Built Heritage
This paper delivers actionable recommendations towards building a rationale for activating and promoting Underground Built Heritage (UBH) based on the nexus heritage, territory and society, and making use of existing literature and findings from five international cases. The research was conducted in the framework of the working group on Planning Approaches of the COST Action Underground4value. The analysis of the cases aims to provide guidelines for this working group and to benchmark good practices in activating UBH. It highlights the importance of community-led initiatives, leadership and dialogue and power sharing between the local/regional authorities and communities aiming for better understanding of the potential of UBH. The successes and/or failures of the five cases emphasise the importance of knowledge and experience in participatory approaches. Success was verified, when effectiveness and democratic principles were combined in the planning process, and local history is integrated with citizen science, co-creation and placemaking. The analysed approaches stimulate a new hybrid layer for activating UBH, provide mechanisms of mediation between people and heritage, and contribute to cultural and social dimensions of sustainability. This is a highly challenging endeavour, as it seeks to support and advance a sound understanding of UBH as a sustainable resource, backed by strategic stakeholder dialogue and contextual knowledge. Such effort requires a dynamic understanding of UBH values, knowledge, abilities and skills, towards creating more effective coalitions of actors within localities, by developing structures, which encourage long term collaborative relationships.
Year: 2021
Number Pages:
15p.
Author(s): Costa, C.; Menezes, M.; Ivanova-Radovanova, P; Ruchinskaya, T.; Lalenis, K.; Bocci, M.
: Sustainability
Editor: MDPI
Volume:
13(18).
Keywords: public participation; place and citizen-based approaches; placemaking; underground heritage
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Betões - Determinação da permeabilidade ao oxigénio
N/A
Year: 2019
Author(s): entidade LNEC
Keywords: Especificação; Betão endurecido; Oxigénio; Ensaio de betão; Permeabilidade do betão
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Materiais históricos: entre tradição e inovação
A caracterização dos materiais históricos e a identificação do respetivo estado de conservação engloba um corpus de conhecimento teórico, prático e metodológico essencial para a conservação e o restauro do património cultural arquitetónico e arqueológico. Refletir sobre os materiais históricos para intervir no património requer, pois, contemplar a variedade de materiais a partir das suas múltiplas facetas, reivindicando uma perspetiva pluri e interdisciplinar na elaboração do conhecimento científico. Requer também aprofundar o estudo das tecnologias e materiais tradicionais, o que contribui para densificar o campo de conhecimento sobre o património e, cientificamente, definir os requisitos de compatibilidade e eficiência dos novos materiais, paralelamente colaborando para a salvaguarda do saber técnico tradicional.
Year: 2019
Author(s): Menezes, M.; Santos Silva, A.
Keywords: Congress; istoric heritage; Archeological heritage /; Architectural heritage; Cultural heritage; Heritage conservation; Materials conservation; Construction material; Cngresso; Património histórico; Património arqueológico; Património arquitetónico; Património cultural; Conservação de património; Conservação de materiais; Material de construção
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PATRIMA_2016
O artigo trata de uma síntese de resultados do Congresso Ibero-Americano Património, suas matérias e imatérias, LNEC, Lisboa, 2-3 de novembro de 2016, constituindo-se um artigo de noticías.
Year: 2017
Number Pages:
1p.
Author(s): Menezes, M.; Costa, D.; Mimoso, J.
: Pedra & CAL
Editor: GECoRPA - Grémio do Património
Volume:
61.
Keywords: Resultados; PATRIMA; Congresso Ibero Americano
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Prefácio do Livro "A supremacia do Pedestre"
O tabalho faz uma apresentação crítica do Livro " A supremacia do Pedestre", da autoria de Fábio Fonseca e Antonio Colchete Filho, tendo o Livro sido editado pela UNALFA: Editora da Unviersidade FEderal de Juiz de Fora, Minas Gerais, Braisl.
Year: 2016
Author(s): Menezes, M.
Keywords: Urbanismo; Planeamento; Cidades criativas; Calçadão; Pedestre
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Determinação do teor de cimento numa amostra de betonilha
É analisada uma amostra de betonilha para determinação do teor de cimento. As análises incluíram a realização de ensaios de resistência à compressão, termogravimetria e químicos.
Year: 2014
Author(s): Ribeiro, A. C.; Santos Silva, A.
Keywords: Resistência à compressão; Teor de cimento; Análise termogravimétrica; Ensaios químicos; Caraterização; Betonilha
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