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Slaked lime is traditionally a suitable material for use in construction activities in historic and traditional buildings whose constitutive characteristics demand compatible and appropriate material solutions. Therefore, knowing the physical and mechanical characterization of lime pastes and mortars for use in restoration is considered an important step in the process of scientific development of a material that, in the Mexican case, has lacked scientific rigor in its production, use and commercialization. With this in mind, the present article aims to investigate the characteristics of lime pastes and mortars that have been used in the traditional way and the new limes that exist in the market, offering suitable options for restoration, for which an integrated methodology was used consisting of physical tests such as surface area, electrical resistivity, pulse velocity, colorimetry, and mechanical tests such as compressive strength, giving as a result that “traditional slaked” lime is more likely to deteriorate than powdered lime, which leads us to conclude that powdered hydrated lime has optimal characteristics for restoration activities.

Lightning strikes are prevalent and inevitable natural phenomena that might cause damages during interaction with building structures and, in some cases, culminate in fires. During the last decades, several lightning strikes have caused considerable damages to cultural and heritage buildings. Furthermore, recent studies indicated a plausible connection between climate changes due to global warming and variations in the frequency and intensity of lightning. The evaluation of the structural efficiency and resilience of cultural buildings to global changes and natural risks appears significant in the light of the current scientific debate. This research aims at the assessment of lightning strikes&rsquo, effects on ancient heritage binding materials through the characterization of their thermal and electrical conductivity properties. This study focused on the performance evaluation of green and low-cost mortars based on the use of organic additives. Lime samples were reverse engineered by using a mixture of organics (fig, jaggery, black grape, banana, kadukai), which comprises the most common additives used in traditional Indian mortars. The reliability of the organic mixture in enhancing the resilience of masonry to lightning strikes was analyzed by using electromagnetic field simulation.

Svijest o kulturnim i ekonomskim vrijednostima baštine raste zadnjih nekoliko desetljeća. Proces obnove ubrzan je velikim razvojem turizma i njegovim utjecajem na ekonomiju pojedinih zemalja. Danas raspolažemo velikim brojem materijala i veziva koje koristimo pri gradnji. Zbog toga je potrebno sve veću pažnju posvetiti izboru pravih materijala i veziva u tijeku restauracije i obnove starih građevina. Treba poštovati načelo izvornosti u pogledu kamena i veziva. Ako to nije moguće potrebno je dobro ocijeniti kakvoću zamjenskih materijala. Fizičko-mehanička i kemijska svojstva morta i kamena moraju biti usklađena. Ukoliko to nije slučaj dolazi do oštećenja ili morta ili kamena ili oba materijala. Njihovim pravilnim izborom povećava se njihova postojanost i trajnost te smanjuju troškovi obnove i održavanja. U ovom radu posebna je pažnja posvećena važnosti pripreme i korištenja tradicionalnih vapnenih mortova. U Europi je njihova korisna primjena ponovno prepoznata i potvrđena. Vapneni su se mortovi često pokazali boljim i trajnijim u složenijim fizičko-mehaničkim i kemijskim uvjetima kakvi vladaju u pojedinim područjima. Vijek vapnenih mortova može se mjeriti stotinama godina. Mortovi u kojima je cement jedno od glavnih veziva u upotrebi su tek nešto više od stotinu godina. Praksa je pokazala da je upotreba cementa kao veziva u mnogim situacijama dvojbena. Odnosi se to na mjesta ugradnje u složenim uvjetima. Cement se i dalje, u manjem ili većem obimu, preporuča upotrebljavati samo na onim mjestima gdje je njegova štetna reaktivnost svedena na minimum., Lime mortars as a most traditional materials have been used for centuries and much before use of cements. Their properties can be enhanced with various ingredients such as breeks, pozzolan and volcanic ash. In the past, lime mortars proved to be very high quality and durable. Lime mortars have been shown to be very stable in very complex physical-mechanical and chemical conditions. Their proper choice increases their aging and durability and reduces construction and maintenance expenses. It is very important that limestone mortar and stone properties must also be harmonized. If this is not the case, damage of mortar or stone or both materials can be expected. Before the start of the work it is necessary to determine the proportion of lime, aggregate and, if necessary, the type of ingredients. Cement continues to be used, at a smaller or greater extent, only in those places where its harmful reactivity could be reduced to a minimum. Traditional lime mortar is very suitable for reconstruction of heritage especially old buildings, forts, walls and sacral monuments.

The addition of new additives and materials to traditional lime mortars may engineer their self-healing capacity, i.e. make them able to repair an occurred mechanical damage. The phenomenon of self-healing may take place both at microscopic and macroscopic level and, in case, can be initiated by a dispersed phase that becomes available as a result of a mechanical damage. The idea underlying this work is hence twofold: first, a mortar is created with a part of the lime protected by an impermeable coating surface, able to make it inert during the phases of setting and hardening; the mechanical characteristic of this material are thus compared to those of a standard mortar. In a second stage, when the material is subjected to an external stress, the protective layer of the treated lime granules, should undergo a rupture which will trigger another step of setting and hardening in the material made dormant by the same treatment. The sealing of the cracks induced by the aforementioned applied stress wil...

Four absorbent mortars were designed in this study and used as sacrificial desalinating media. The mortars comprised lime, sepiolite, nanosilica (72/3/25 by weight) and three admixtures (H2O2 and two commercial aerators) and had a liquid/solid ratio of 0.9, a mean porosity of 40% and a mean pore size of 0.8–0.7 μm. These mortars were applied three times to ashlars exhibiting surface saline efflorescence on a church at Talamanca del Jarama, a town in the Spanish province of Madrid. The salts impregnating the wall were characterised with XRD, FTIR and Micro-Raman spectroscopy. The ion concentrations in the ashlars was studied with ion chromatography at 0.5 cm, 1.5 cm and 3.0 cm from the surface after each application and the inner and outer surfaces of the mortars were analysed with Micro-Raman spectroscopy to determine the desalinating efficacy of the mortars. The mortars designed mobilised and absorbed the soluble salts in the ashlars; as a rule, elimination was most effective in anions with a smaller ionic volume and therefore greater ionic mobility and when the salt concentration was high and superficially located. Three years after application of the desalinating mortars, the salt concentration in the ashlars treated was 50% lower than prior to treatment., This study was funded by the Regional Government of Madrid’s ‘Geomateriales 2’ programme (S2013/MIT2914) under the CLIMORTEC project (BIA2014-53911-R).

Three dumped raw materials, a tuff and two bentonites, obtained from two mining sites at the North Bohemian basin in the Czech Republic, have been studied in order to evaluate them as pozzolanic admixtures in lime mortars for employment in restoration of cultural heritage objects. After thermal activation (800 °C; 5 h), their pozzolanic properties were compared with those of commercial metakaolin. Quantitative phase analysis with the Rietveld method from X-ray powder diffraction patterns, morphological observations, as well as the Frattini and the modified Chapelle tests were performed. In addition, lime mortars, incorporating the fired materials, were prepared and subjected to simultaneous thermal analysis after a 28-day initial curing (20 ± 1 °C; 60 ± 5 % RH). The results showed that all three materials possess pozzolanic activity. However, when employed in lime mortars they did not result in formation of pozzolanic reaction products. Two methods were proposed to improve their reactivity; grinding to obtain finer particle size and removal of quartz content where necessary.DOI: http://dx.doi.org/10.5755/j01.ms.23.1.14864

Recently, the use of lime mortars in the restoration of historic buildings has found a renewed interest because they can guarantee the required mechanical, chemical and physical compatibility with the existing substrate. Spontaneous occurrence of self-healing phenomena in lime-based mortars is well known; the possibility of engineering the self-healing capacity, through tailored additions, is therefore of the utmost interest with the aim of enhancing the durability of the building masonry restoration works. This work proposes a system for the evaluation of the self-healing capacity with reference to traditional and advanced lime mortars. The autogenous healing capacity of a reference lime mortar has been first of all evaluated. Then, the possibility of engineering the aforementioned capacity has also assessed, through both commercial crystalline admixtures and tailored encapsulated additives. These should work according to a twofold mechanism: first, the coated granules envelope a core of lime mortar with purpose of making it inert during the hardening phase. Secondly, once the coated granules rupture upon cracking and damage of the mortar, the reactive binder is released and undergoes a delayed hardening, which is responsible of the healing phenomena. The results show that the mortar is able to heal micro-cracks; moreover, the addition of the crystalline admixture enhances this capacity. The different kinds of employed coated granules were also able to induce a sensible self-healing, but they decrease the instantaneous compressive strength.

Absolute dating of mortars is crucial when trying to pin down construction phases of archaeological sites and historic stone buildings to a certain point in time or to confirm, but possibly also challenge, existing chronologies. To evaluate various sample preparation methods for radiocarbon (14C) dating of mortars as well as to compare different dating methods, i.e.14C and optically stimulated luminescence (OSL), a mortar dating intercomparison study (MODIS) was set up, exploring existing limits and needs for further research. Four mortar samples were selected and distributed among the participating laboratories: one of which was expected not to present any problem related to the sample preparation methodologies for anthropogenic lime extraction, whereas all others addressed specific known sample preparation issues. Data obtained from the various mortar dating approaches are evaluated relative to the historical framework of the mortar samples and any deviation observed is contextualized to the composition and specific mineralogy of the sampled material.

Lime renders are of great importance not only to enhance the appearance of the buildings, but also to protect and preserve old masonries. They constitute a specialized system, composed of several layers, in which each of them depends on the others and carries out some specific functions in order to assure a suitable performance of the whole. Knowledge of the traditional materials and techniques, as well as the know-how, is one of the key points in the maintenance and conservation of lime renders and, by extension, of our Heritage. However, the promotion of the use of cement and the industrialization process, which in the case of Spain took place about the 1960's, caused lime mortars to fall into disuse. In this article, classical treatises as well as the state-of-the-art researches were analysed to compile the properties of lime render layers, on the whole. The knowledge of these characteristics is essential to maintain and repair the existing renders as well as to formulate new compatible ones, while assuring their durability and appropriate performance. Lime is the selected binder for these recommendations because it was widely used as drawn from the literature. ispartof: Journal of Cultural Heritage vol:15 issue:3 pages:326-330 status: published

[EN] Researchers have related the manufacturing technique of plasters and stucco in the Maya area with their period of production but not with their architectural function. In this paper, we establish a relationship between those three features (manufacturing technique, age, and architectural function) in the plasters of the Maya site of Dzibanche in southern Quintana Roo. Dzibanche has abundant remains of stuccos and plasters found mainly in three buildings (Plaza Pom, Pequena Acropolis, and Structure 2). We used thin sections, SEM and XRD, and archaeomagnetic dating processes. The pictorial layer of Structure 2 was the earliest (AD 274-316 and the stuccoes and plasters of the other two buildings were dated to the Middle Classic (AD 422-531), but we obtained different archaeomagnetic dates for the red pigment layers found in the buildings of the Pequena Acropolis and thus we were able to determine their chronological order of construction. The raw materials and proportions were carefully chosen to fulfil the mechanical necessities of the architectonic function: different proportions were found in plasters of floors, in the external walls, and inside the buildings; differences between earlier and later plasters were also detected., We acknowledge the archeological project of Dzibanche and Centro INAH Quintana Roo who generously allowed the extraction of the samples for this study; also we acknowledge the Universidad Nacional Autonoma de Mexico that gave a grant that allowed a three month research in the laboratories of the Universitat Politecnica de Valencia. Financial support for the analysis of organic materials is kindly acknowledged; it was provided by the Spanish MINECO R+D project CTQ2014-53736-C3-1-P and also supported with ERDEF funds. The authors thank Jaime Diaz for his assistance in preparing thin sections.

The systematic analysis of mortars from monuments or historic buildings and the simultaneous study of the construction environment show that it was common practice to use naturally occurring sand from local rivers or streams for the production of the mortars. There are cases though, mainly on islands, where sands of natural origin were limited, and marine or crushed sands were used possibly after elaboration. In all cases the particle size analysis of old mortar confirms the presence of even distribution of the granules. As regards the design of the repair mortars, there are criteria that should be taken into consideration in order to produce materials with compatible properties. The main properties concerning sands are the grain distribution and maximum size, the color, the content of fines, and soluble salts. The objective of this research is the study of the physical characteristics of the sands such as the sand equivalent, the gradation, the apparent density, the morphology of the grains, their mineralogical composition and the influence of these properties on the behavior of lime mortars, notably the mechanical and physical properties acquired.

Lime mortars can suffer alterations when subjected to gaseous pollutants. Particulate air pollutants can also be deposited and incorporated to the mortar surfaces. Thus, they can be used as pollution tracers allowing us to measure deposition rates of pollutants to compare pollution loads. To calculate deposition rates the absolute age of the studied mortars must be known. Luminescence dating allows estimating the age of lime mortars but involves some partially unsolved problems. Luminescence yields the age of an object from the ratio between paleodose or cumulative radiation dose in the minerals of that object and the annual dose rate of ionizing radiation. The development of optically stimulated luminescence (OSL) in the last years and the application of statistical tools have resulted in the first dating of lime mortars. In this work mortars from old buildings and have been collected from two urban sites (A Coruña, Spain, and Braga, Portugal) to estimate their ages by luminescence. Thus, the mortars could be used as passive samplers to calculate deposition rates and relate these to different pollution loads. Results show partial successful estimates and some related problems in younger mortars are discussed., Fundação das Universidades Portuguesas e Ministerio de Ciencia e Innovación (Espanha) através da “Ação Integrada E-141/10"/“Acción Integrada PT2009-0077” (Espanha), Projeto PUDC10N04 da Universidade de A Coruña, Fundação para a Ciência e Tecnologia (programa plurianual de financiamento das unidades de investigação; fundos nacionais).

The incorporation of phase change materials (PCM) into traditional mortars give to these products theability to store and release heat. In this way it is possible to reduce the energy consumption and improve the thermal comfort in buildings. The introduction of micro and nanomaterials in the mortars matrixcan cause microstructural changes that need to be addressed in order to optimize the PCM addition. The relationship between the hardened state performance of different PCM-mortars, its internal microstructure and pore distribution as been observed for different binders such as lime, cement and gypsum. Their hardened state properties, microstructural modifications and heat storage capabilities were evaluated.The ability to store and release heat depends strongly on the size and distribution of internal pores andnot only on the PCM content. Using a thermal efficiency test, an important correlation between thermal performance and the mortars microstructure was established, for mortars with 0–30% of PCM added., Fundação para a Ciência e a Tecnologia (FCT)

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007, Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2007, Sürdürülebilir yapı üretimi bilincinin, yapı malzemesi üretiminden başlayarak dikkate alınması gerekir. Günümüz yapı üretiminde yaygın olarak tüketilen çimentonun yüksek maliyeti ve çevreye olumsuz etkileri değerlendirildiğinde, alternatif malzeme-bağlayıcı araştırmaları gereği ortaya çıkmaktadır. En eski yapı malzemelerinden olan puzolanlı kireç harçlarının yüksek durabilite özelliklerine karşın, ortam sıcaklığında kürlendiklerinde yavaş dayanım kazanmaları, kullanımlarının azalmasına neden olmuştur. Bu bağlamda kireç harcının yapısal kullanımının yaygınlaştırılması, çalışmanın amaçlarından biridir. Diğer yandan, genleştirilmiş perlit olarak yapı sektöründe kullanılmakta olan malzemenin genleştirilmeden, puzolanik özeliğinden yararlanılarak kullanılması olanaklarının araştırılması ve kullanımının yaygınlaştırılması bu çalışmanın ana amacıdır. Bu çalışma kapsamında, perlitin puzolanik aktivitesine etki eden parametrelerin belirlenmesi, bu parametrelerin, aktiviteyi artırıcı yönde geliştirilmesi olanakları araştırılmıştır. Saptanan en uygun kompozisyonlar üzerinde puzolanik aktiviteyi geliştirecek yöntemlerin belirlenmesi, katkı maddeleri ile puzolanik etkinliğin geliştirilmesi olanakları incelenmiştir. İyileştirilmiş perlitli kireç harcının yapı malzemesi için gerekli durabilite özelliklerinin tespiti için kapiler su emicilik, ağırlıkça ve hacimsel su emicilik, buhar geçirgenlik, donma-çözünme dayanımı, rötre deneyleri yanında puzolanik tepkime sonunda meydana gelen hidratasyon ürünlerini tespit etmek amacıyla XRD ve DTA-TG analizleri yapılmıştır. Deneye dayalı bu araştırma ile elde edilen bulgular ve bu bulguların değerlendirilmesi sonucunda, amaca uygun nitelikte iç yapı bloğu ve harç elde edilebildiği saptanmıştır., The consciousness of sustainability of production of buildings, should be considered beginning from building materials production. When the high cost and the unconstructive negative environmental affects of the frequently used material cement is considered, the certain need for a research of an alternative adherent material appears. Although, one of the oldest construction materials; pozzolanic lime mortars, have high durability, the long term strength development caused to decrease of its usage. In this context, one of the aims of this study is widespread of use of lime mortars in construction. On the other hand, the main objective of this study is to expand the use of perlite as a raw material in construction sector as a natural pozzolanic material , without dilatation which currently is used as. In this study, determining the parameters of perlite effecting pozzolanic activity, and developing these parameters on increasing the features of activity, have been the main objective. Determination of the methods to develop increase of the pozzolanic activity on the most convenient compositions and the effectiveness of pozzolanic activity with additives is studied. To determine the necessary durability features of the perlite lime mortar, capillary water absorption, absorption by weight and volume, vapor diffusion, freeze-thaw durability, and in addition to these, the XRD and DTA-TG analyses to ascertain the hydration products caused by pozzolanic reactions have also been done. The results of this experimental study indicate that the prepared mortars are convenient for restorations of historical masonry and inner side brick., Doktora, PhD

[EN]New repair mortars with biocide properties were subjected to acid rain wet/dry cycles in aggressive environment simulation chambers. Those mortars based on lime had a sepiolite addition as a biocide support. The aim of this work was to determine the influence of both the clay and the biocide on mortar behaviour under aggressive solutions. The aggressive solutions used were the following: 1) H2SO4 solution, with pH = 4.5; and 2) “acid rain” solution with pH = 3.5. In the first case (H2SO4 solution), neither the sepiolite nor the biocide had a significant influence on mortar behaviour, while in the second aggressive medium (“acid rain”), sepiolite plus biocide, a decrease in the reaction between the mortar and the “acid rain” were noted.

[EN]It is well known that the presence of pollution increases the degradation of some building materials. In order to understand the influence of individual pollutants as well as the role of oxidants and water in lime mortar degradation, those materials have been exposed in atmospheric simulation chambers. According to the pollutants used in the chambers (NO, NO2 and SO2), NO2− and NO3− or SO32−and SO42− have been analysed and related with the reaction between the lime mortar and the pollutant. The reactivity order of the different pollutant (NO, NO2 and SO2), in presence and absence of water and/or oxidant has been determined.

[EN] The behaviour of lime mortars containing sepiolite or sepiolite plus pentaclorophenol in atmospheric simulation chambers has been studied. The pollutant gases used in this study have been NO, NO2, and SO2. The studies has been done in wet and dry conditions as well as with and without ozone. In the case of NO and NO2, the aggressive agent would be HNO3, which reacts with lime mortar binder CaCO3, producing Ca(NO3)2 formation. On this process, the influence of the presence of an oxidant as well as water has been studied. The catalyst effect of the oxidation is known to be accelerated by water presence, so mortars exposed to NO + O3 + H2O and NO2 + O3 + H2O environments undergo a greater salts formation than those exposed to the rest of the aggressive media. The three mortars’ behaviours are similar and independent of their composition, producing small amount of salts in every case. When SO2 is the gas used, the aggressive agent of mortar will be H2SO4 that reacts with mortar binder, CaCO3 to produce calcium sulphate in the form of gypsum. Oxidant and/or water influence has been studied, and the (SO2 + O3 + H2O) chamber was found to be the one with greater aggressivity to mortars. However, in these conditions, sepiolite presence within the mortars delayed gypsum formation.