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Air lime mortars with vegetable fat addition : characteristics and research needs

Shasavandi, Arman; Salavessa, Eunice; Torgal, Fernando Pacheco; Jalali, Said
Fonte: RILEM Publication Publicador: RILEM Publication
Tipo: Conferência ou Objeto de Conferência
Publicado em 22/09/2010 ENG
Relevância na Pesquisa
57.15%
Although history reveals that air lime mortars with added vegetable fat (ALVF) were used very often in the past, little knowledge about them survives to modern times. Little is known about the influence of fat addition on the mortars’ durability, and some details about their manufacture and application are completely unknown. Even less is understood about the mechanisms that explain the behavior of ALVF-based mortars that also contain pozzolans. This paper reviews current knowledge about the characteristics of ALVF-based mortars in order to highlight questions that must be addressed in future research.

Parametrical studies of the behavior of aerial lime mortars; Estudos paramétricos do comportamento de argamassas de cal aérea

Guimarães, Erika Tinoco
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Trabalho de Conclusão de Curso
Publicado em //2014 ENG
Relevância na Pesquisa
57.28%
Dissertação de mestrado integrado em Civil Engineering; Aerial lime has been largely used as binder in mortars before the emergence of Portland cement, being commonly found in historic constructions. The contemporary interest in aerial lime mortars has enlarged concerning the field of structural restoration, given its compatibility with traditional materials. The process through which lime hardens is the carbonation reaction. Aiming to understand the influence of environmental conditions on carbonation, the current work extends a previously developed study on the behaviour of aerial lime mortars, in view backing multiphysics simulation models and obtaining modelling parameters. Systematic studies on the effect of relative humidity, carbon dioxide concentration and carbonation rate throughout time were followed by modifying the environments of exposure of specimens and comparing the results. Carbonation has been investigated using thermo gravimetric analysis and phenolphthalein staining. Additionally, drying and water transport mechanisms were assessed through humidity profiles monitoring. Mechanical properties have also been evaluated and discussed in view of chemical investigation results.; A cal aérea foi muito utilizada como ligante de argamassas antes do surgimento do cimento Portland...

Influence of curing conditions on lime and lime-metakaolin mortars

Faria, Paulina; Martins, Ana Isabel G.
Fonte: Repositório Comum de Portugal Publicador: Repositório Comum de Portugal
Tipo: Conferência ou Objeto de Conferência
Publicado em /04/2011 ENG
Relevância na Pesquisa
47.58%
Comunicação apresentada ao XII DBMC - International Conference on Durability of Building Materials and Components, Porto, April 12th-15th, 2011; Air-lime mortars with or without pozzolanic components were largely used in historic buildings. Due to natural or accidental degradation it is often necessary the application of repair mortars, durable and compatible with the masonries of historic buildings. Within this context and associating the improvement of mortars characteristics to the necessity of sustainable construction practices, some mortars formulated with lime and the addition of pozzolans have been studied. In previous papers, the influence of some types of air-lime (powder hydrated lime or lime putty) and the addition of metakaolin in lime mortars have been presented. Each type of mortar presents its specificities. In pure lime mortars the setting occurs by carbonation and in lime-metakaolin mortars it occurs both by carbonation and hydration. A crucial question in order to optimize the characteristics of the mortars (and its applicability) is related with the curing conditions. This article describes an experimental campaign with different pure air lime mortars and lime-metakaolin mortars, cured under different conditions of relative humidity and CO2 content. Properties of the mortars...

Current mortars in conservation: an overview

Faria, Paulina
Fonte: International Journal for Restoration Publicador: International Journal for Restoration
Tipo: Artigo de Revista Científica
Publicado em //2004 ENG
Relevância na Pesquisa
57.19%
Renders are an important item in historical buildings and the need for their periodical re-application is a basic conservation procedure. In modern times there has been a trend towards the replacement of traditional pure lime mortars by new formulations including Portland cement or hydraulic lime. Apart from those interventions on specific and very important monuments, in which the use oftraditional non-hydraulic mortars can be enforced, in most of the projects involving less than first order magnitude heritage the use of some sort of hydraulic components is becoming the rule rather than the exception. The present paper describes and analyses the results of an experimental study with ten formulations of current mortars - including some that can hardly be considered as adequate conservation procedures - allowing a direct comparison in terms of some of the most relevant characteristics.

Lime-metakaolin mortars for historical buildings repair: study of the hardening reaction

Faria, Paulina; Gameiro, A.; Santos-Silva, A.; Veiga, R.; Velosa, A.
Fonte: LNEC Publicador: LNEC
Tipo: Artigo de Revista Científica
Publicado em /07/2012 ENG
Relevância na Pesquisa
57.22%
International Conference Durable Structures: from construction to rehabilitation. Lisbon, LNEC, 31 May-1 June 2012; Formulation of mortars with adequate durability and strength is nowadays one of the major challenges in historical buildings repair. Pozzolanic materials have been used during centuries in air lime mortars to improve their mechanic and durability characteristics. This paper is part of an extensive work being developed in Portugal, aiming to characterize lime-metakaolin mortars to be employed for historical buildings conservation and repair. This paper presents the results of hardening reaction study until 90 days of curing in humid conditions. The results show that in the adopted curing conditions, the hydration reaction occurs mostly for early ages of curing (28 days) while the carbonation reaction is mostly dominant for longer ages (90 days).

Lime based mortars for ceramic tile application: the influence of the lime, the use of a metakaolin and the curing

Faria, Paulina; Silva, Vitor; Grilo, J.; Bandeira, A.; Branco, T.; Mergulhão, D.
Fonte: Univ. Aveiro Publicador: Univ. Aveiro
Tipo: Artigo de Revista Científica
Publicado em /10/2012 ENG
Relevância na Pesquisa
47.52%
Intern.Conference AZULEJAR, Univ. Aveiro, 10-12 October 2012; Bearing in mind the need to repair ceramic tile facade, that were traditionally applied by a lime-based mortar, an experimental campaign was held in order to characterize over time mortars made with two types of lime - an air lime EN 459-1 CL90-S and a recently classified EN 459-1 NHL3.5. The influence of different binder: aggregate proportions on mortars with air lime, of different percentages of a metakaolin substituting the same weight of air lime or of natural hydraulic lime and of different curing conditions are tested and discussed. Mortars used to apply glazed ceramic tiles will have a low contact with the carbon dioxide of the environment and the hardening of pure air lime mortars will be difficult. For that reason the addition of a metakaolin on air lime-based mortars can be advantageous. But natural hydraulic lime mortar NHL3.5 have registered higher mechanical strength but comparable capillary suction and drying characteristics to air lime mortars; that is why NHL mortars, without or with a low amount of metakaolin, can also be a possibility to intervene glazed ceramic tile façade when the mechanical resistances are compatible.

Influence of lime type and curing conditions on lime and lime-metakaolin mortars

Faria, Paulina; Martins, Ana
Fonte: Freitas, Vasco Peixoto de, Delgado, J.M.P.Q. (Eds.)/Springer-Verlag Publicador: Freitas, Vasco Peixoto de, Delgado, J.M.P.Q. (Eds.)/Springer-Verlag
Tipo: Parte de Livro
Publicado em //2013 ENG
Relevância na Pesquisa
47.51%
Durability of Building Materials and Components (Vasco Peixoto de de Freitas, J.M.P.Q. Delgado, eds.), Building Pathology and Rehabilitation, vol. 3, VIII, 105-126. ISBN: 978-3-642-37474-6 (Print) 978-3-642-37475-3 (Online). Springer-Verlag Berlin Heidelberg. DOI: 10.1007/978-3-642-37475-3_5; Air-lime mortars with or without pozzolanic components were largely used in the past. Due to natural or accidental degradation it is often necessary the application of repair mortars, durable and compatible with the masonries of histor-ic buildings. Within this context and associating the improvement of mortars char-acteristics to the necessity of sustainable construction practices, mortars formulat-ed with limes and the addition of pozzolans have been studied. Each type of mortar presents its specificities. In pure lime mortars the setting oc-curs by carbonation and in lime-metakaolin mortars it occurs both by carbonation and hydration. A crucial question in order to optimize the characteristics of the mortars (and its applicability) is related with the curing conditions, which potenti-ate differently the reaction and consumption of the calcium hydroxide. This article describes an experimental campaign with different pure air lime mor-tars and lime-metakaolin mortars...

Influence of curing conditions in lime-metakaolin blended mortars – A mineralogical and mechanical study

Cardoso, Daniel; Gameiro, André; Santos-Silva, António; Faria, Paulina; Vieira, Ricardo; Veiga, Rosário; Velosa, Ana
Fonte: Historic Mortars Conference Publicador: Historic Mortars Conference
Tipo: Artigo de Revista Científica
Publicado em /09/2013 ENG
Relevância na Pesquisa
57.35%
3rd Historic Mortars Conference, 11-14 September 2013, Glasgow, Scotland; The need to formulate mortar compositions with adequate durability and compatibility is nowadays one of the major challenges in historical buildings repair. The incorporation of pozzolanic materials as addition or replacement of lime is viewed as a solution to these challenges regarding the increase in hardening time, mechanical strength, water resistance and durability. This paper includes part of an extensive work being developed in Portugal, which has the objective of developing and characterizing lime-metakaolin mortars for conservation purposes. This paper evaluates the influence of the curing conditions, namely medium and high relative humidity (HR), lab and outdoor exposition, and direct daily contact with potable or sea water. Two air lime mortars with volumetric proportion 1/3 of binder and aggregate, with 0 and 9% metakaolin (mass % replacement of air lime) were characterized up to one year of age. The mortars evolution with curing was followed by XRD, TG-DTA, tensile and compressive strength tests. The humid and urban curing revealed the best results in terms of the pozzolanic reaction, occurring mostly at lower curing times (28 days), although carbonation reaction is dominant throughout all ages up to 1 year.

Viability of ceramic residues in lime-based mortars

Matias, Gina; Faria, Paulina; Torres, Isabel
Fonte: Historic Mortars Conference Publicador: Historic Mortars Conference
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2013 ENG
Relevância na Pesquisa
67.56%
3rd Historic Mortars Conference, 11-14 September 2013, Glasgow, Scotland; When we approach the subject of construction and rehabilitation of buildings we necessarily must think about external wall coatings as they are the elements more exposed to climate actions, mechanical and environmental conditions and, consequently, the first to be deteriorated and to need rehabilitation. In what concerns the replacement of old plasters and renders, air lime mortars are normally the ones that are more compatible with the existing elements, but that have some limitations due to its slow setting time. As an alternative we may use natural hydraulic lime mortars. We know that brick dust and grains have been widely used in mortars in the past, improving its characteristics, and that actually there are many kinds of ceramic residues that are byproducts of industry and are normally carried into landfills. Within this context and associating the improvement of mortars characteristics to the necessity of sustainable construction practices, some mortars, formulated based on air lime or natural hydraulic lime, with the addition of ceramic residues, have been recently studied. The aim of this paper is to present the experimental work that has been developed concerning the behaviour of two types of these lime mortars with ceramic residues. Characteristics...

Natural hydraulic lime mortars: influence of the aggregates

Faria, Paulina; Silva, Vitor
Fonte: Historic Mortars Conference Publicador: Historic Mortars Conference
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2013 ENG
Relevância na Pesquisa
57.32%
3rd Historic Mortars Conference, 11-14 September 2013, Glasgow, Scotland; Natural hydraulic lime specifications changed with the new version of standard EN 459-1: 2010 and a new Portuguese NHL3.5 appeared in the market. The characteristics of mortars depend on many different parameters such as the type of binder, the type of aggregates, the use of fillers and of superplasticizers; also on mixing and curing conditions. In this paper NHL3.5 mortars with binder:aggregate volumetric proportions1:3 were prepared, varying the aggregates type and proportions between them. Two coarse sands, a medium sand, a river sand, a finer sand, a calcareous filler and a ceramic powder were used. The two last mentioned aggregates were byproducts from industry. Prismatic mortar samples and samples of mortar applied over brick were prepared and conditioned in two different situations – following standard EN 1015-11 and at 65% relative humidity with initial daily water spray. Mortars were characterized in the fresh state and at the age of 28 days. Results showed the influence namely of the curing, particularly in terms of water capillary, of the superplasticizer and of the fillers. They also showed that NHL3.5 mortars seem to be adequate for old masonries conservation and repair and...

Comparative evaluation of aerial lime mortars for architectural conservation

Faria, Paulina; Henriques, Fernando M.A.; Rato, Vasco
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2008 ENG
Relevância na Pesquisa
57.31%
Journal of Cultural Heritage 9 (2008) 338-346; International bibliography on conservation usually refers that mortars made with lime putty with long extinction periods behave better than others made with the current dry hydrated limes. In order to evaluate this assess, an experimental study of lime mortars was carried out, using dry hydrated lime and two lime putties. It becomes clear that the use of lime putties with long extinction periods in mortars allow better performances, particularly in applicability and resistance to sulphates.

The influence of brick residues in the behaviour of lime mortars

Matias, Gina; Faria, Paulina; Torres, Isabel
Fonte: Subrata Chattopadhyay, Oktay Ural (Eds.); Indian Institute of Technology Kharagpur Publicador: Subrata Chattopadhyay, Oktay Ural (Eds.); Indian Institute of Technology Kharagpur
Tipo: Conferência ou Objeto de Conferência
Publicado em /11/2008 ENG
Relevância na Pesquisa
57.36%
XXXVI IAHS World Congress on Housing - National Housing Programs-New Visions, November 03–07, 2008, Kolkata, India; Mortars have a great repercussion on the durability of a masonry construction due to its protective role. The compatibility among the masonry materials (the masonry units, the mortar of the joints, the plasters and the renders) incites the adequate behaviour of the wall and consequentially an increase in durability. Very often we came across with rehabilitation errors due to the use of incompatible mortars whether with the pre-existing mortar or with the others wall materials, which can origin great pathologies. Repair mortars should be compatible with existent materials. Old mortars were normally air lime based and sometimes had in their composition some other products like brick dust which confer specific properties. Small grains of brick residue can take the role of a particular aggregate and brick dust of a pozzolan, reacting with the calcium hydroxide of the air lime and improving the mortars behaviour. Simultaneously its application has the great advantage of reuse an industrial by-product. With the increasing environmental concerns it is important to find appropriate solutions to the industry residues. In this way we can contribute for a better use of the material resources and to the decrease of deposition of residues in landfills by studying its performance as part of a repair mortar. The propose of this paper is to present the results obtained in an experimental work developed at the University of Coimbra which main goal was to analyze the influence of brick residues coming from an industrial plant in the behaviour of lime mortars to be applied as repair mortars...

Lime mortars with brick dust and grounded particles for ancient masonry: development and evaluation

Matias, Gina; Faria, Paulina; Torres, Isabel
Fonte: LNEC Publicador: LNEC
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2008 ENG
Relevância na Pesquisa
57.57%
HMC08 - 1st Historical Mortars Conference: Characterization, Diagnosis, Conservation, Repair and Compatibilit, LNEC, Lisbon, 24-26 September 2008; Lime mortars with brick dust and grounded particles have been largely used in many regions of the world as plasters, renders and in masonry joints and repointing. In Portugal this type of pozzolanic mortars has been introduced at least since the Roman period, particularly when hydraulic characteristics were needed. Brick dust, a source of silica and also of alumina, react with the calcium hydroxide of the lime, resulting on silicates and aluminates of calcium hydrates. The brick particles (grounded to appropriate dimensions) will act as a specific aggregate. The lime mortars with brick material are supposed to achieve hydraulic characteristics and increment their mechanical resistances and durability, compared to pure lime mortars. Also the mortar behavior in face of water (liquid and vapor) will be changed. Lime mortars with brick material also present compatibility with ancient supports, what does not happened with cement mortars. Within this context and associating the improvement of mortars characteristics to the necessity of sustainable construction practices, some mortars formulated with lime and the addition of industrial by-products have been recently studied by several researchers. To present pozzolanic reactivity...

Lime mortars with rice husk ash for ancient masonry

Almeida, Nuno G.; Faria, Paulina; Pinto, Ana Paula
Fonte: LNEC Publicador: LNEC
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2008 ENG
Relevância na Pesquisa
57.4%
HMC08 - 1st Historical Mortars Conference: Characterization, Diagnosis, Conservation, Repair and Compatibility, LNEC, Lisbon, 24-26 September 2008; This paper presents some preliminary results achieved in the aim of a research program with the main objective of evaluating the potential interest of using rice husk ashes on aerial lime based mortars for old buildings. The mechanical and physical characteristics and potential durability of lime mortars formulated with commercial rice husk ashes are analysed and their behaviour compared with a pure lime mortar. The results are also analysed taking into account the main aspects that are responsible for the compatibility between the new mortars and the original building materials. The potential durability of the tested mortars is evaluated through salt crystallization tests performed with sodium chloride and sodium sulphate solutions. The improvement of some properties of the lime mortars due to the presence of rice husk ashes pointed out the interest of the research in this domain, namely in what concerns the design of mortars with a moderately hydraulic behaviour for old buildings.

The effect of hydraulic components on lime mortars

Faria, Paulina; Henriques, Fernando M.A.
Fonte: O. Ural, V. Abrantes, A. Tadeu (eds.) Publicador: O. Ural, V. Abrantes, A. Tadeu (eds.)
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2002 ENG
Relevância na Pesquisa
67.21%
XXX IAHS World Congress on Housing - Housing Construction: An Interdisciplinary Task, September 9-13, 2002, Coimbra, Portugal; In order to allow a better knowledge and an easier use of lime mortars for the conservation of historic buildings a research program is being carried out, in which the effects of hydraulic components on lime mortars are evaluated. The hydraulic components used in this study are natural pozzolan, fly ashes and both material for ceramic tiles production and kaolin, after being fired at different temperatures. This paper presents the results obtained with one formulation prepared with each of the different hydraulic components, emphasising the great influence of the curing conditions in the results and the benefits obtained in comparison with a pure hydrated lime mortar.

New natural hydraulic lime mortars – Physical and microstructural properties in different curing conditions

Grilo, João; Faria, Paulina; Veiga, Rosário; Santos-Silva, António; Silva, Vitor; Velosa, Ana
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /01/2014 ENG
Relevância na Pesquisa
57.08%
Construction and Building Materials 54 (2014) 378–384; The new version of EN 459-1 standard for building limes redefined the classes of hydraulic limes and made the producers reformulate or reclassify their natural hydraulic limes. This work evaluates the mechanical, physical and microstructural behavior of mortars formulated with a recently produced natural hydraulic lime NHL3.5 that conforms to EN 459-1, submitted to natural marine environment, humid and standardized conditions, and also the benefits and drawbacks of adding metakaolin in partial replacement of lime. Mortars with NHL3.5 present positive results at young ages. The metakaolin addition increases strength while decreasing the capillary water coefficient. The behavior in an aggressive marine environment seems promising.

Lime mortars with ceramic wastes: characterization of components and their influence on the mechanical behaviour

Matias, Gina; Faria, Paulina; Torres, Isabel
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /12/2014 ENG
Relevância na Pesquisa
57.27%
Considering the fundamental importance of preserving the built heritage and of ensuring the good performance achieved by incorporating ceramic particles in lime mortars in ancient times, it is important to study solutions that use materials the available today, in order to produce mortars intended to repair and replace the old ones. Solutions incorporating industrial ceramic waste might be profitable for several reasons, namely for economic, environmental and technical aspects. In this paper, seven ceramic waste products collected from ceramics factories are characterized. Their mineralogy, dimensional features and pozzolanicity were determined. Three of these products, with different particle size fractions (obtained directly from milling, dust only and fragment fractions only), were selected, incorporated into air lime mortars, and their mechanical strength was determined. In the present work, evidence of mechanical efficiency, when common sand or air lime were partially replaced by ceramic wastes, was made clear, drawing attention to the sustainability of this type of mortars, hence, encouraging further research.

Long-term characterization of air lime mortars with ceramic waste

Matias, Gina; Torres, Isabel; Faria, Paulina
Fonte: O. Ural, V. Abrantes and A. Tadeu (eds.); ITeCons Publicador: O. Ural, V. Abrantes and A. Tadeu (eds.); ITeCons
Tipo: Artigo de Revista Científica
Publicado em /12/2014 ENG
Relevância na Pesquisa
57.38%
Due to their exposure to environmental conditions, outer coatings composed by render and painting system are usually the first construction elements to deteriorate and require intervention. A correct conservation and rehabilitation of these materials is fundamental once they provide protection to other façade materials. It is known that old mortar renders were essentially air lime based mortars. To maintain the integrity of the whole wall-render elements, the image of the building and to avoid accelerated degradation, conservation and rehabilitation must be implemented with compatible mortars. As that, lime based mortars would be preferable. It was also common, in ancient renders, the incorporation of ceramic residues, which is, nowadays, an abundant material, especially in Central Region of Portugal. The reuse of these materials has great relevance once their landfilling causes serious environmental issues. In an attempt to combine the environmental and technical advantages of the use of ceramic waste in mortars’ production for rehabilitation purposes, a research has been developed at the University of Coimbra, in cooperation with Nova University of Lisbon, on the long term behaviour of air lime mortars with ceramic residues. In this paper the most significant up to one year results of an experimental campaign with air lime mortars with 1:3 and 1:2 volumetric proportions and ceramic residues are presented.

Estudo do mecanismo de aderência de azulejos e argamassas de cal em revestimentos históricos; Study of the bond mechanism between glazed tiles and lime mortars in historic coatings

JAPIASSÚ, Pammila
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Geotecnia e Construção Civil; Engenharias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Geotecnia e Construção Civil; Engenharias
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
57.38%
The historical glazed tiles facades are an important luso-brazilian cultural expression that must be conserved and preserved. The bonding loss of glazed tiles to laying mortars is one of the most critical pathologic manifestations of this kind of coating. However, despite this importance, there‟s still a lack of studies about the bonding mechanism between this historical components. Accordingly, this dissertation proposed to perform an experimental and exploratory research, which the main objective is to give some contribution to the understanding of the ancient tile‟s bonding mechanism to the aerial lime-based mortar of historical buildings facade. For this, were analyzed samples of facade historical ceramic coating, between the late XIX and early XX century, of Ovar‟s buildings, in Portugal. In order to reproduce the historical bonding mechanism, were also analyzed ceramic coating applied in laboratory studying mortars of rehabilitation. In the first stage, were analyzed the ceramic coating and the mortars historic of three cases, as well was performed the interface‟s study between this two materials. In the second stage, were produced ceramic coatings in laboratory using tiles (similar to the historical ones) and four types of mortars of rehabilitation...

Fresh state characterization of lime mortars with PCM additions

Lucas, S.; Senff, L.; Ferreira, V. M.; Aguiar, J. L. Barroso de; Labrincha, J. A.
Fonte: Applied Rheology Publicador: Applied Rheology
Tipo: Artigo de Revista Científica
Publicado em //2010 ENG
Relevância na Pesquisa
67.27%
The application of sustainability principles in construction encourages the development of new products, with new functionalities and applications, able to improve buildings environmental performance. The use of latent heat storage materials in lime mortars aims to reduce the energy consumption of buildings. This work intends to evaluate the impact of phase change materials (PCM) incorporation in rheological and hardened state properties of aerial lime mortars. A fresh state characterization was conducted through the rheological study complemented with flow table tests of different mortar formulations. To complete the mortar characterization some hardened state properties (porosity, mechanical strength and microstructure) after 28 days, were also evaluated. It was concluded that, the PCM microcapsules incorporation does not compromise aerial lime mortars overall performance and may help to improve some characteristics like workability and mechanical strength. Therefore, it is possible to reduce the energy demand in old buildings, improving their performance and sustainability.; Die Anwendung von Nachhaltigkeitsprinzipien im Baubereich fördert die Entwicklung neuer Produkte mit neuen Funktionen und Anwendungen, die die Umweltbilanz von Gebäuden verbessern können. Die Anwendung von versteckten Wärme speicher materialien in Kalkmörteln hilft...