Miembros del Grupo
Coordinador
Colaboradores
Líneas de Investigación
- Materiales descontaminantes. Matrices de cal y de cemento con propiedades descontaminantes: aditivos fotocatalíticos. Morteros autolimpiantes. TiO2 y derivados sensibles a la luz visible
- Nuevos morteros de cal para restauración del Patrimonio Cultural edificado: morteros de cal con aditivos y adiciones puzolánicas. Morteros de cal de resistencias mejoradas
- Recubrimientos multifuncionales activos para materiales de construcción y del Patrimonio Arquitectónico: propiedades superhidrofóbicas, de protección frente a la humedad y de autolimpieza
- Retención de metales tóxicos en matrices de cemento. Utilización como agentes de solidificación/estabilización de cemento de aluminato. Cementos de aluminato y fosfato como agentes retenedores. Ensayos de lixiviación
Palabras Clave
- Aditivo
- Cal
- Cemento
- Encapsulación
- Fotocatálisis
- Lixiviación
- Mortero
- Puzolánico
Publicaciones Científicas desde 2018
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Autores: Tena Santafe, Víctor Manuel; Fernández Álvarez, José María; Fernández Acevedo, Claudio; et al.Revista: CATALYSTSISSN: 2073-4344 Vol.13 N° 11 2023 págs. 1-27ResumenThe aim of this study was to develop versatile coatings that can protect the stone surfaces of Ar-chitectural Heritage. Two different 3D media, namely superhydrophobic (SPHB) and hy-dro-oleophobic (OHB), were utilized as host matrices for nanostructured photocatalysts (Bi2O3-ZnO 8/92). These photocatalysts were sensitive to visible light to enhance their efficiency when exposed to sunlight. To prevent the nanophotocatalyst from clumping together in the 3D media, non-ionic dispersant additives (Tween20, TritonX-100, and Brij35) were incorporated. The optimized suspensions were then applied to various substrates such as sandstone, limestone, and granite. The effectiveness of the coatings was assessed by evaluating the hydrophobicity, oleo-phobicity, and photocatalytic activity of the coated substrates. The Bi2O3-ZnO photocatalyst exhib-ited higher activity in the SPHB medium compared to the OHB medium. To simulate real-life con-ditions, the coated substrates were subjected to accelerated weathering tests to predict their dura-bility. Despite a significant reduction in their thickness, the coatings demonstrated sustained hy-drophobic efficiency and self-cleaning capability after the accelerated ageing tests.
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Autores: Pavia, S. (Autor de correspondencia); Veiga, R.; Hughes, J.; et al.Revista: MATERIALS AND STRUCTURESISSN: 1359-5997 Vol.56 N° 4 2023 págs. 87ResumenIt is believed that many historic mortars were made using hot-lime mixing techniques. They are back in use today, and their good qualities are often praised, including being more compatible and a better match with historic fabrics. This paper studies the methods of producing hot-lime mortars and putties. It discusses the variables that determine the properties of the resultant mortars such as slaking and calcination, and compares hot-lime mortars with their equivalent putties, and with factory-produced calcium lime and hydraulic lime mortars. The paper concludes that the most important variable that governs the properties of hot-lime mixed mortars is the quantity of water used for slaking, because it determines the temperature reached during slaking which makes the resultant Ca(OH)2 vary from a fairly large size to extremely small, hence producing mortars with different properties. Based on scientific and historic evidence, it is concluded that the best method for hot-lime mixing is dry-slaking (sand-slaking) with long storage, because it combines a high slaking temperature (that reduces particle size and increases the surface area of the hydrate), with gradual slaking (that lowers volume expansion and crack development) and long storage (to ensure complete slaking hence no expansion cracks). Many historic mortars were probably hot-lime mixed. However, it is practically impossible to recreate them today due to the different limestones, kilns, calcination regimes and slaking/storage methods used in the past. Hydraulic and magnesian quicklimes were used historically for hot-mixing. In contrast, most of the factory quicklimes used today are purer limes with higher free lime content and a greater reactivity. Therefore, a hot-lime mix made with a factory-produced quicklime may not be more authentic or compatible than a natural hydraulic lime ¿NHL¿ mortar designed to suit a specific fabric and application. To ensure quality mortars that can be consistently repeated, a hot-lime mixing specification should contain both the process and the materials including: type of slaking (dry/wet); amount of water used; mixing details and the time at which it takes place; storage time and at what stage does it occur. To control the slaking temperature, the right amount of water should be established (according to free lime content) by trial which will also inform on the amount of yield and hence allow proportioning. With careful site work and specification, high-quality, compatible mortars can be made with both NHLs and hot-lime mixing. However hot-lime mixing requires more time and logistics, closer care and a more complicated specification.
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Autores: Lozano-Lunar, A.; Otero, R.; Álvarez Galindo, José Ignacio; et al.Revista: APPLIED CLAY SCIENCEISSN: 0169-1317 Vol.238 2023 págs. 106938ResumenThis research deals with the immobilisation of lead-contaminated waste by means of the Double Barrier Technique. Specifically, the integral treatment of lead-contaminated water is studied by incorporating Layer Double Hydroxides (one calcined and two uncalcined) into cement monoliths. The three Layer Double Hydroxides were composed of Mg-Al in the layer, the calcined with carbonate in the interlayer, and the other two with nitrate or meso-2,3-dimercaptosuccinic acid, respectively. In the first stage of research, the influence of Layer Double Hydroxides and lead on the heat of hydration in cement pastes was analysed. Subsequently, mortars were produced to evaluate compressive strengths, mineralogy and leaching behaviour in monolithic and granular state. The interaction of sulphate ion played an important role in delaying the first stage of hydration. However, the presence of Layer Double Hydroxides counteracted the detrimental effect of lead on the cementitious materials. The compressive strength was modified by Layer Double Hydroxides and lead, less than 5 MPa in all cases, being in line with the heat of hydration. The mineralogical study determined the formation of the same mineral phases in all cementitious systems (with and without Layer Double Hydroxides). Mortars were environmentally classified as "Inert" in monolithic state. Mortar with Mg-Al in the layer and meso-2,3-dimercaptosuccinic acid in the interlayer was classified as "Non-Hazardous" in granular state reducing the mobility of lead to the medium by 50% with respect to the lead-doped mortar without Layer Double Hydroxides content. The results obtained in this research show the sustainability of the Double Barrier Technique as it achieves an immobilisation of lead-contaminated water while maintaining the criteria of release levels below the established limits.
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Autores: Álvarez Galindo, José Ignacio (Autor de correspondencia); Veiga, R.; Martínez-Ramírez, S.; et al.Revista: MATERIALS AND STRUCTURESISSN: 1359-5997 Vol.55 N° 2 2022 págs. 75
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Autores: Groot, C. (Autor de correspondencia); Veiga, R.; Papayianni, I.; et al.Revista: MATERIALS AND STRUCTURESISSN: 1359-5997 Vol.55 N° 10 2022 págs. 245ResumenFor conservation interventions of historic masonry generally lime-based mortars such as pure air lime mortars, lime-pozzolan mortars, natural hydraulic lime mortars and ternary mortars (lime-pozzolan-cement) are used. The main reason is that their hygric and mechanical (strength and ductility) performance are easy to adapt to most existing historic masonry (compatibility requirements). Although the basic appropriateness of lime-based mortars for restoration is undisputed, there are also some limitations in the application of these mortars. In this report a review is given of the theoretical backgrounds and further of laboratory research developments in the field of lime-based binders and mortars over the past decades. Furthermore, practical experiences in positive and negative sense (damage cases) are elaborated. Drawbacks and points of attention are being dealt with, which are essential for a durable application of lime-based mortars for the conservation of historic masonry. In general, it is concluded that points of attention should be addressed through a thorough evaluation of their potential and through testing of their suitability. For these mortars, even more than for modern cement-based mortars, specifically, environmental exposure conditions and application conditions should be considered.
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Autores: González Sánchez, Jesús Fidel; Fernández Álvarez, José María; Navarro Blasco, Íñigo; et al.Revista: CONSTRUCTION AND BUILDING MATERIALSISSN: 0950-0618 Vol.271 2021 págs. 121887ResumenThe present work presents focuses on the use of different admixtures for the development of rendering lime-based mortars with improved adhesion and durability, as well as reduction of cracking. To this aim, combinations of an adhesion improver (ethylene-vinyl acetate copolymer, EVA), a water repellent agent (sodium oleate), a viscosity enhancer (a starch derivative) and a mineral admixture (pozzolanic addition of nanosilica or metakaolin) were tested. The renders were applied on four different substrates (sandstone, limestone, granite and brick) to assess their performance. The influence of the admixtures¿ combination on fluidity, stiffening time, adhesion, cracking, compressive strength, pore structure, frost resistance and durability against magnesium sulfate attack was evaluated. The EVA admixture was seen to enhance the adhesion when used in combination with oleate, metakaolin and starch. This combination also led to a minimized cracking. Opposite trends between adhesion and cracking were observed as a function of the porosity of the substrates and of the presence of small-sized capillary pores. The interferences with the carbonation accounted for the drops observed in compressive strength for the nanosilica-free tested renders; nanosilica-containing renders showed good compressive performance, due to the filling effect of the admixture and to the C-S-H formation.
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Autores: Lozano-Lunar, A.; Álvarez Galindo, José Ignacio; Navarro Blasco, Íñigo; et al.Título: Optimisation of mortar with Mg-Al-Hydrotalcite as sustainable management strategy lead wasteRevista: APPLIED CLAY SCIENCEISSN: 0169-1317 Vol.212 2021 págs. 106218ResumenThis study analyses how a Mg-Al-Hydrotalcite with carbonate in the interlayer influences the hydration of mortar allowing the management of lead waste (solid or liquid) in a cement-based material. First, the compatibility of hydrotalcite with the cementitious matrix was studied through heat of hydration, workability, consistency, compressive strength and mineralogical phase formation. The changes produced by the incorporation of hydrotalcite were not drastic and the compatibility with the cement was verified. Lead was added in oxide and nitrate form to mortar with or without hydrotalcite and the same properties were evaluated, including a leaching test. The incorporation of lead delayed the hydration, this effect being increased by the hydrotalcite, which happened in the first instants of hydration. The addition of hydrotalcite counteracted the negative effect of lead in compressive strength values. The interaction between the hydrotalcite and the lead waste was favoured by the formation of plumbites under the pH conditions of cement hydration. Consequently, this interaction would seem to be superficial. The lead leaching decreased to values included in the "Non-Hazardous" limit of the environmental classification, very close to "Inert". All mortars were produced by two mixing procedures to establish differences. When hydrotalcite was included, the compressive strength was higher in the second procedure and lead leaching showed better behaviour in the first procedure.
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Autores: Etxebeste Mitxeltorena, Mikel; Moreno Amatria, Esther; Carvalheiro, M.; et al.Revista: ACS INFECTIOUS DISEASESISSN: 2373-8227 Vol.7 N° 12 2021 págs. 3197 - 3209ResumenLeishmaniasis urgently needs new oral treatments, as it is one of the most important neglected tropical diseases that affects people with poor resources. The drug discovery pipeline for oral administration currently discards entities with poor aqueous solubility and permeability (class IV compounds in the Biopharmaceutical Classification System, BCS) such as the diselenide 2m, a trypanothione reductase (TR) inhibitor. This work was assisted by glyceryl palmitostearate and diethylene glycol monoethyl ether-based nanostructured lipid carriers (NLC) to render 2m bioavailable and effective after its oral administration. The loading of 2m in NLC drastically enhanced its intestinal permeability and provided plasmatic levels higher than its effective concentration (IC50). In L. infantum-infected BALB/c mice, 2m-NLC reduced the parasite burden in the spleen, liver, and bone marrow by at least 95% after 5 doses, demonstrating similar efficacy as intravenous Fungizone. Overall, compound 2m and its formulation merit further investigation as an oral treatment for visceral leishmaniasis.
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Autores: González Sánchez, Jesús Fidel; Tasci, B.; Fernández Álvarez, José María; et al.Revista: JOURNAL OF CLEANER PRODUCTIONISSN: 0959-6526 Vol.292 2021ResumenThe aim of this study is to develop new air lime mortars with enhanced photocatalytic depolluting and self-cleaning abilities. Nanosilica, as pozzolanic mineral admixture, was used to improve the strength of mortars, whereas nanotitania (TiO2) was added to impart photocatalytic properties. At the same time, five different dispersing admixtures -superplasticizers- were added in bulk to the mortars to enhance the photocatalytic activity by reducing the rate of charge carrier recombination. Four polycarboxylate-based derivatives and a polynaphthalene sulfonate were tested aiming to achieve an efficient charge separation. In order to increase the lasting of the mortars subjected to water movements, sodium oleate was also added as a water repellent agent. Since the photoinduced hydrophilicity, responsible for the self-cleaning effect, might be affected by the water repellent, the compatibility between this admixture and the photocatalytic performance of the nanotitania was also investigated. Results showed that photocatalytic activity was improved due to the action of the superplasticizers as indicated by an average 33% increase of NO degradation, which is significant to the depolluting activity of these mortars. Furthermore, these mortars also showed a greatly reduced release of intermediate toxic compounds, mainly NO2: the selectivity factor (NOx/NO) reached values up to 87%.
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Autores: Álvarez Galindo, José Ignacio (Autor de correspondencia); Veiga, R.; Martínez-Ramírez, S.; et al.Revista: MATERIALS AND STRUCTURESISSN: 1359-5997 Vol.54 N° 2 2021 págs. 63ResumenThe main objective of RILEM TC LHS-277 "Specifications for testing and evaluation of lime-based repair materials for historic Structures" is the revision, adaption and, when necessary proposal, of the test methods to accurately study lime-based binding systems and mixtures, such as mortars and grouts. The empiric use of the lime-based composites and the predominant employ of cement in the field of Civil Engineering have led to the widespread application of test methods developed for cement-based composites to test the former. However, the clear differences in composition and performance between modern cement binders and lime-based materials would advise to explore specific test methods for the latter. To undertake this task the previous knowledge on the mechanisms of setting and hardening of these binders must be revised, arranged and synthesized. Processes such as drying, carbonation, hydration and pozzolanic reaction may occur during the setting and hardening of lime-based mortars and competition between them cannot be underestimated. With the aim of underpinning the revision and proposal of test methods for lime-based systems, this review paper reports a comprehensive study of the mechanisms of setting and hardening of these binders, considering the variability of the composition, which includes pure air lime as well as lime with hydraulic properties, lime-cement and lime-pozzolan systems.
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Autores: Álvarez Galindo, José Ignacio (Autor de correspondencia)Revista: INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGEISSN: 1558-3058 Vol.14 N° 7 2020 págs. 943 - 947
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Autores: González Sánchez, Jesús Fidel; Tasci, B.; Fernández Álvarez, José María; et al.Revista: POLYMERSISSN: 2073-4360 Vol.12 N° 4 2020 págs. 887ResumenThis paper presents the experimental procedure to develop air lime-based injection grouts including polymeric superplasticizers, a water repellent agent and pozzolanic agents as additives. Research focuses on the development of grouts to improve various characteristics simultaneously combining different additions and admixtures. Aiming to improve the injectability of the grouts, in this study different polymeric superplasticizers were added, namely polycarboxylated-ether derivative (PCE), polynaphthalene sulfonate (PNS) and condensate of melamine-formaldehyde sulfonate (SMFC). Sodium oleate was also used as a water repellent agent to reduce the water absorption. The enhancement of the strength and setting time was intended by using microsilica and metakaolin as pozzolanic mineral additions. Compatibility between the different admixtures and action mechanism of the different polymers were studied by means of zeta potential and adsorption isotherms measurements. Diverse grout mixtures were produced and investigated assessing their injectability, fluidity, stability, compressive strength, hydrophobicity and durability. This research leads to several suitable mixtures produced by using more than one component to enhance efficiency and to provide better performance of grouts. According to the results, the grout composed of air lime, metakaolin, sodium oleate and PCE was found the most effective composition improving the mechanical strength, injectability and hydrophobicity.
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Autores: Speziale, A.; González Sánchez, Jesús Fidel; Tasci, B.; et al.Revista: INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGEISSN: 1558-3058 Vol.14 N° 7 2020 págs. 1008 - 1029ResumenUnique multifunctional coatings, comprising a 3D superhydrophobic agent and two nanostructured photocatalysts (solar-light sensitive 50/50 and 10/90 TiO2-ZnO nano-heterostructures), compatible with the inorganic substrates of the Built Heritage, have been designed. The synthesized nanoparticles showed an enhanced photocatalytic activity (tested by NO degradation) as compared with the raw TiO2 and ZnO materials. Dispersing agents were used to optimize the coatings, avoiding agglomeration of the photocatalytic nanoparticles and increasing the stability of the suspensions. Four distinct dispersions were optimized and applied as coatings onto stony materials used in the Built Heritage, such as sandstone, lime mortar, granite and limestone. Their effectiveness was assessed by assessing hydrophobicity of the surfaces (static water contact angle), photocatalytic activity and self-cleaning as well as water vapour permeability of the treated specimens. These transparent coatings demonstrated high compatibility with the construction materials of the Architectural Heritage and showed a synergistic effect rendering a minimized water absorption, self-cleaning ability evidenced by the reduced adsorption of soiling deposits and a reasonable degradation of any trace that might be adsorbed, as well as a protecting hydrophobic environment for the photocatalyst.
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Autores: Lozano-Lunar, A.; da Silva, P. R.; de Brito, J.; et al.Revista: JOURNAL OF CLEANER PRODUCTIONISSN: 0959-6526 Vol.219 2019 págs. 818 - 832ResumenThis study analyses the feasibility of incorporating electric arc furnace dust (EAFD) in the production of self-compacting mortars from the point of view of durability. Two types of EAFD, previously characterized and classified as hazardous waste, were used. Siliceous filler (powder) was replaced at different ratios (25%, 50%, and 100%, by volume). The following self-compacting mortar properties were measured at different curing times: total heat of hydration, compressive strength, ultrasonic pulse velocity, pore size distribution through mercury intrusion porosimetry, shrinkage and mass loss, water absorption by capillary, water absorption capacity, bulk density, skeletal density, open porosity for water, wettability by contact angle measurement, electrical resistivity, and carbonation depth. Although some of properties linked to the durability of the mortars, such as water absorption by capillarity, wettability or carbonation, were negatively affected by the incorporation of the EAFD, the results show the feasibility of replacing siliceous filler at up to 25% and the valorisation of EAFD as a secondary raw material (SRM). This research demonstrated that EAFD can be used as SRM as an alternative to landfills, thereby contributing to the promotion of the new circular economic model pursued by the European Union.
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Autores: Esquinas, A. R.; Álvarez Galindo, José Ignacio (Autor de correspondencia); Jiménez, J. R.; et al.Título: Durability of self-compacting concrete made from non-conforming fly ash from coal-fired power plantsRevista: CONSTRUCTION AND BUILDING MATERIALSISSN: 0950-0618 Vol.189 2018 págs. 993 - 1006ResumenThe search for answers to the environmental challenges is one of the obligations of the current society. Therefore, the optimisation of natural resources and the minimisation and revaluation of waste should be present in any activity. These purposes should be included in both the construction and energy sectors owing to the large amount of resources consumed and of pollutants and waste generated by them. The present work carries out a feasibility study of the use of fly ash from coal-fired power plants as a filler for self-compacting concrete (SCC). This kind of fly ash does not meet the compliance criteria determined by the regulations, and thus, it is non-conforming fly ash (NCFA). The dual objective of this work is the optimisation of a natural non-renewable resource and the recovery of waste, which should achieve the qualification of end of waste before being used as a by-product. For this purpose, a comparative study of three mixes is performed, namely, SCC-1 with commercial siliceous filler (SF) (SCC reference), SCC-12 with a mix 1:1 by volume of SF and NCFA, and SCC-2 with NCFA. All the mixes showed good self-compactability. The analysis of the relevant parameters, i.e., apparent and dry density, open porosity, mercury intrusion porosimetry, absorption of water by immersion, and capillarity, has been significant to know in depth the durability of the mixes.
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Autores: Santos, A. R. (Autor de correspondencia); Veiga, M. R.; Santos Silva, A.; et al.Revista: CONSTRUCTION AND BUILDING MATERIALSISSN: 0950-0618 Vol.187 2018 págs. 907 - 922ResumenThe pore structure of air lime mortars, formulated with aggregates of different mineralogy and grain size distribution, was evaluated with the aim of studying the influence of sand type on the microstructural modification over time and of establishing the relationship between these modifications and the mechanical behaviour. The microstructure of the mortars was determined by mercury intrusion porosimetry at 28, 90 and 360¿days, and the results were compared with its mechanical characteristics, namely compressive strength, flexural strength and modulus of elasticity. A remarkable increase of mechanical strength over time was found for all mortars. An optimized grain size distribution of the sand (optimized compactness) proved to be favourable to air lime mortars compared with grain size distribution defined by standard EN 196-1, showing a good behaviour of the interlocked structure but also adequate porosity that favours lime carbonation. A relationship between the mechanical properties and the porous structure was also established: large volumes in the range of macropores tend to reduce the mechanical strength while gel pores, related with the presence of hydraulic compounds, are generally linked to an increase in strength. Overall, the assessment of the microstructure indicates that the packing density and the shape of the aggregates are the dominant parameters influencing the pore size distribution of macropores;
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Autores: Pérez Nicolás, María; Plank, J.; Ruiz-Izuriaga, D.; et al.Revista: CONSTRUCTION AND BUILDING MATERIALSISSN: 0950-0618 Vol.162 2018 págs. 628 - 648ResumenCoatings made with water dispersions of different nano-particles of photocatalytic additives (titania and titania doped with iron and vanadium) were prepared with diverse superplasticizers, SPs, to optimize the atmospheric NO removal efficiency when applied onto cement- and air-lime mortars. The use of different polycarboxylate-based superplasticizers (52IPEG, 23APEG and 45PC6) prevented nano-particles from agglomeration. The steric hindrance, provided by a large density and length of side chains, was ascertained as the most effective repulsion mechanism and 52IPEG was the most efficient SP. In PC- and air-lime mortars, the coatings with polycarboxylate-based SPs improved the NO removal rates as compared with the SP-free coating: an average increase of NO degradation by 15% under UV and by 76% under solar light was found. This finding was related to the drop in the agglomeration of the photocatalysts, with more exposed active sites and a decrease of the electron-hole recombination rates. Capillary water absorption and water vapour permeability values showed that the coatings did not alter the performance of the mortars. SEM examination showed that the use of SPs enhanced the distribution of the photocatalysts yielding thinner coating layers and boosting the percolation of the active material within the mortars. Accelerated weathering showed a moderate reduction of NO removal efficiency. Coating with 52IPEG was the most efficient in preserving the activity. Measurements of Ti content showed a low washout of the TiO2 nano-particles, supporting the long-run activity of these coatings.
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Autores: Durán Benito, Adrián; González Sánchez, Jesús Fidel; Fernández Álvarez, José María; et al.Revista: POLYMERSISSN: 2073-4360 Vol.10 N° 8 2018 págs. 824ResumenA new range of grouts prepared by air lime and metakaolin (MK) as a pozzolanic admixture has been obtained by using as dispersing agents two polymers, namely poly-naphthalene sulfonate (PNS) and lignosulfonate (LS), with the aim of improving the fluidity of the fresh grouts. Fluidity and setting times of the grouts were assessed. Differences in the molecular architecture and in the anionic charge density explained the different adsorption of the polymers and the different performance. The higher anionic charge of PNS and its linear shape explained its better adsorption and effectiveness. The pozzolanic reaction was favoured in grouts with PNS, achieving the highest values of compressive strength (4.8 MPa after 182 curing days). The addition of PNS on lime grouts slightly decreased the frost resistance of the grouts (from 24 freeze-thaw cycles for the polymer-free samples to 19 or 20 cycles with 0.5 or 1 wt % of PNS). After the magnesium sulphate attack, grouts were altered by decalcification of hydrated phases and by formation of hexahydrite and gypsum. A protective role of portlandite against magnesium sulphate attack was clearly identified. Accordingly, the polymer LS, which preserves a significant amount of Ca(OH)2, could be an alternative for the obtaining of grouts requiring high sulphate attack resistance.
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Autores: Esquinas, A. R.; Álvarez Galindo, José Ignacio; Jimenez, J. R. (Autor de correspondencia); et al.Título: Durability of self-compacting concrete made with recovery filler from hot-mix asphalt plantsRevista: CONSTRUCTION AND BUILDING MATERIALSISSN: 0950-0618 Vol.161 2018 págs. 407 - 419ResumenIn construction, there is a need to respond to environmental challenges and implement the Circular Economy as a strategy for the sustainable growth of the sector. To eliminate the lack of confidence in the application of the waste from this sector, it is necessary to carry out research in order to achieve an effective and integral management, as well as the reuse and recycling of these materials. In this work, a detailed study of Self-Compacting Concrete (SCC) was carried out, using as filler a waste from the drying process of the aggregate used in the manufacture of hot-mix asphalt. The results showed that it is possible to obtain a high-performance SCC in terms of durability by replacing a commercial siliceous filler (SF) with this dolomitic residual powder (RF), with high performance against the attack of aggressive agents (chloride, sulphate and carbonate ions) and shrinkage. In this study the analysis of the physical parameters of the materials (density, open porosity and pore size distribution as obtained from mercury intrusion porosimetry) and water absorption (by immersion and capillarity) was fundamental. The joint analysis of all the studied parameters allowed obtaining exhaustive results about the durability of the mixes and its interrelation with the properties of the constituents. (C) 2017 Elsevier Ltd. All rights reserved.
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Autores: Rubio Aguinaga, Andrea; Fernández Álvarez, José María; Navarro Blasco, Íñigo; et al.Libro: Conservation and Restoration of Historic Mortars and Masonry StructuresISSN: 978-3-031-31471-1 2023 págs. 567 - 581ResumenMicroencapsulated Phase Change Materials (PCMs) were included in air lime rendering mortars in order to improve the thermal comfort of the inhabitants and the energy efficiency of buildings of the Architectural Heritage under the premises of minimum intervention and maximum compatibility. Three different PCMs were tested and directly added during the mixing process to fresh air lime mortars in three different percentages: 5, 10 and 20 wt. %. Some chemical additives were also incorporated to improve the final performance of the renders: a starch derivative as an adhesion booster; metakaolin as pozzolanic addition to shorten the setting time and to increase the final strength; and a polycarboxylated ether as a superplasticizer to adjust the fluidity of the fresh renders avoiding an excess of mixing water. The specific heat Cp, the enthalpy ¿H ascribed to the phase change and the melting temperature of the PCMs were determined by Differential Scanning Calorimetry (DSC). The capacity of the renders to store/release heat was demonstrated at a laboratory scale. The favourable results proved the effect of these PCMs with respect to the thermal performance of these rendering mortars, offering a promising way of enhancement of the thermal efficiency of building materials of the Cultural Heritage.
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Autores: Rubio Aguinaga, Andrea; Fernández Álvarez, José María; Navarro Blasco, Íñigo; et al.Libro: Conservation and Restoration of Historic Mortars and Masonry StructuresISSN: 978-3-031-31471-1 2023 págs. 582 - 598ResumenDifferent batches of repair lime rendering mortars were designed by mixing microencapsulated Phase Change Materials (PCMs) and other additives. The final aim of these renders is to improve the thermal efficiency of the envelope of the Built Heritage, while allowing the practitioners to apply a render with positive final performance. The combinations of the PCMs in different weight percentages, a superplasticizer (to increase the fluidity of the render keeping constant the mixing water), an adhesion improver and a pozzolanic additive were studied. The adhesion of these renders onto bricks and limestone specimens and the shrinkage and cracking of the mortars were studied in detail. X-ray diffraction technique was used to study the composition and evolution of the carbonation process. Compressive strength measurements were studied in hardened specimens. In addition, the porous structure of the rendering mortars was studied by mercury intrusion porosimetry to assess the effect of the PCMs¿ addition. Results have shown that these thermally enhanced mortars are feasible materials for real-life application in the context of architectural heritage restoration and conservation.
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Autores: Rubio Aguinaga, Andrea; Fernández Álvarez, José María; Navarro Blasco, Íñigo; et al.Libro: Proceedings of the 6th Historic Mortars Conference - HMC 2022ISSN: 978-961-6884-77-8 2022 págs. 620 - 633ResumenMicroencapsulated Phase Change Materials (PCMs) were introduced in air lime rendering mortars in order to improve the thermal comfort of the inhabitants and the energy efficiency of buildings of the Architectural Heritage under the premises of minimum intervention and maximum compatibility. PCMs were directly added during the mixing process to fresh air lime mortars in three different percentages: 5, 10 and 20 wt. %. Some chemical additives were also incorporated to improve the final performance of the renders: a starch derivative as an adhesion booster, metakaolin as pozzolanic addition to shorten the setting time and to increase the final strength; and a polycarboxylate ether as a superplasticizer to adjust the fluidity of the fresh renders avoiding an excess of mixing water. The specific heat Cp, the enthalpy ¿H ascribed to the phase change and the melting temperature of the PCMs were determined by Differential Scanning Calorimetry (DSC). The capacity of the renders to store/release heat was demonstrated at a laboratory scale, proving by thermal conductivity measurements the effectiveness of PCMs for the reduction of gaps between peak and offpeak thermal loads as well as for the delay in the appearance of the peaks. The favourable results proved the effect of these PCMs with respect to the thermal performance of these rendering mortars, offering a promising way of enhancement of the thermal efficiency of building materials of the Cultural Heritage.
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Autores: Rubio Aguinaga, Andrea; Fernández Álvarez, José María; Navarro Blasco, Íñigo; et al.Libro: Proceedings of the 6th Historic Mortars Conference - HMC 2022ISSN: 978-961-6884-77-8 2022 págs. 634 - 648ResumenDifferent batches of repair lime rendering mortars were designed by mixing microencapsulated Phase Change Materials (PCMs) and other additives. The final aim of these renders is to improve the thermal efficiency of the envelope of the Built Heritage, while allowing the practitioners to apply a render with positive final performance. The combinations of the PCMs in different weight percentages, a superplasticiser (to increase the fluidity of the render keeping constant the mixing water), an adhesion improver and a pozzolanic additive were studied. The adhesion of these renders onto bricks and limestone specimens and the shrinkage and cracking of the mortars were studied in detail. X-ray diffraction technique was used to study the composition and evolution of the carbonation process. Compressive strength measurements were studied in hardened specimens. In addition, the porous structure of the rendering mortars was studied by mercury intrusion porosimetry to assess the effect of the PCMs¿ addition. Samples underwent accelerated climatic ageing to study their durability and the preservation of the thermal efficiency. Results have shown that these thermally enhanced mortars are feasible materials for real-life application in the context of architectural heritage restoration and conservation.
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Autores: González Sánchez, Jesús Fidel; Tasci, B.; Martínez de Tejada de Garaizábal, Guillermo; et al.Libro: RILEM Proceedings PRO 130ISSN: 978-235158-221-3 2019 págs. 359 - 372ResumenDifferent rendering mortars were prepared by mixing air lime and air lime-pozzolanic nanosilica with TiO2 and sodium oleate as, respectively, photocatalytic and water repellent agents, added in bulk. The aim of the work was to design and obtain new rendering mortars with improved durability focusing in the reduction of the water absorption of these materials and in their self-cleaning and biocide effect. To achieve a better distribution of the TiO2 particles, which was expected to enhance their efficiency, different dispersing agents were also incorporated to the fresh mixtures. Four diverse polycarboxylate ethers superplasticizers and a poly-naphthalene-sulfonate were tested. Workability and fluidity of the fresh rendering mortars were determined to guarantee the applicability of the final products. Water contact angle was monitored with the aim of assessing the hydrophobicity of the mortars lent by the water repeller. The biocide effect was studied by means of the culture of a strain of Pseudomonas fluorescens. The colonization of the mortars¿ surface was analyzed by determining the number of colonies forming units (CFU) after several days subjecting the samples to suitable T and RH conditions. At the same time, the surface of the mortars was irradiated with solar light to activate the photocatalyst. Results showed the efficiency of the sodium oleate in reducing the water uptake of the rendering mortars.
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Autores: Veiga, R.; Stefanidou, M.; Balksten, K.; et al.Libro: Proceedings of the International Conference on Sustainable Materials Systems and Structures (SMSS2019) Durability, Monitoring and Repair of StructuresISSN: 978-2-35158-218-3 Vol.3 N° 128 2019 págs. 629 - 636ResumenLime based mortars used for the repair and renovation of old lime renders have important functions in historic buildings, such as the protection of the masonry and aesthetics of the surfaces. Hence, they have a significant contribution to the durability of the walls, which often are structural elements. Cracking and loss of adherence are two of the most severe defects for renders, as they drastically affect their functional capacity. Cracking is related to shrinkage, elastic characteristics, and kinetics of the gain of strength as well as to water transport properties of the render. Most of these aspects are governed by the porous structure of the mortar, which is a function of the composition of the mix and application issues. Loss of adherence is related to the compatibility of the render with the substrate, concerning mechanical, thermal and hygric aspects. Loss of cohesion, due to leakage of the binder, freeze-thaw, salts crystallization or other causes, results in significant damage, difficult to repair. The appearance of stains either by pollutants deposition or by biocolonization is also a concern related to durability of renders. In the present paper the degradation mechanisms leading to cracking, loss of adhesion or cohesion and stains formation are analysed based on literature, and a review of assessment test methods are carried out. Finally, the need for test improvement in this area is highlighted.
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Autores: González Sánchez, Jesús Fidel; Navarro Blasco, Íñigo; Durán Benito, Adrián; et al.Libro: Proceedings PRO 130 : 5th Historic Mortars ConferenceISSN: 978-235158-221-3 2019 págs. 330 - 345ResumenThis work reports the obtaining of lime-based grouts as repairing materials. Microsilica was added as pozzolanic additive to enhance the compressive strength of the hardened grouts. Sodium oleate, as water repellent admixture, and different superplasticizers (SPs) were also incorporated to reduce the water absorption and to enhance the injectability of the grouts. Polycarboxylate ether (PCE), polynaphthalene sulfonate (PNS), melamine sulfonate (MMS) and polyacrylic acid (PA) were tested as SPs. Regarding the fluidity of the grouts, PCE was seen to improve the injectability, followed by PNS, MMS and PA. However, PCE addition was also accompanied by a severe delay in the setting time. The other three superplasticizers did not provoke significant delays in the hardening of the samples. The water contact angle underwent an increase pointing to an effective hydrophobization of the surface as a consequence of the water repellent admixture. The combination with PCE was the most effective in keeping the water repellency in comparison with the control sample (lime grout + oleate). MMS yielded high compressive strengths and durability of the mortars, in the face of freezing-thawing cycles, was enhanced.
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Autores: Speziale, A.; González Sánchez, Jesús Fidel; Navarro Blasco, Íñigo; et al.Título: Active photocatalytic-superhydrophobic coating with TiO2-ZnO nano-heterostructures for lime mortarsLibro: Proceedings PRO 130 : 5th Historic Mortars ConferenceISSN: 978-235158-221-3 2019 págs. 155 - 168ResumenActive coatings to be applied onto hardened surfaces of lime rendering and masonry mortars and stones of the Built Heritage were developed. Nano-heterostructures of TiO2/ZnO (50:50 and 10:90) were obtained by Flame Spray Pyrolysis as photocatalytic agents with expanded sensitivity towards solar light, instead of the restricted UV dependence of the pure TiO2 or ZnO. A superhydrophobic medium was simultaneously prepared and photocatalytic nanoparticles were added to obtain the coatings. The active products were expected to prevent the water absorption of the substrates and the subsequent degradation effects as well as to allow the stones and mortars to act as self-cleaning materials, reducing the dirt deposition and the biological colonization. Dispersions were applied onto the surface of lime mortars and siliceous stone. Measurements of the photocatalytic oxidation activity of the coatings were carried out by means of the NO degradation, showing a very good efficiency of the nanoparticles even at long term tests (values of NO oxidation of ca. 35%). Water contact angle assessment evidenced a strong hydrophobization of the treated surfaces, with WCA values higher than 140º. The results proved the synergistic effect of these coatings with respect to the durability of the treated substrates, giving rise to a promising way of preventive conservation for building materials of the Cultural Heritage.
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Autores: Papayianni, I.; Valek, J.; Álvarez Galindo, José Ignacio; et al.Libro: Proceedings of the International Conference on Sustainable Materials, Systems and Structures (SMSS2019) : Durability, Monitoring and Repair of StructuresISSN: 978-2-35158-218-3 N° 128 2019 págs. 135 - 139ResumenLime-based mortars (LM(s)) seem to be preferred in repairing historic structures. The long-term performance of repair LM(s) is closely related to durability issues concerning the old structure substrate, the new repair mortars and interface between the two aforementioned materials, which is also much influenced by the technique of mortars application. Durability is a multifunctional property affected by a number of parameters, including local environmental conditions. However, experience showed that some of the characteristics of materials play a dominant role in assessing the durability of repair LM(s) and have a direct impact on longevity of the repaired structure.
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Autores: González Sánchez, Jesús Fidel; Navarro Blasco, Íñigo; Durán Benito, Adrián; et al.Libro: Tradición, versatilidad e innovación en la cal: un material de excelenciaISSN: 978-84-8081-604-5 2018 págs. 251 - 262ResumenLos morteros de relleno o inyección, especialmente destinados a reparación de cavidades y defectos de albañilería, deben fluir adecuadamente en estado fresco y combinar resistencia y durabilidad. Para conseguir algunas de estas características pueden utilizarse aditivos químicos: superplastificantes, para mejorar la fluidez; adiciones puzolánicas, para conseguir resistencias adecuadas en ambientes con limitado acceso de CO2 y una mejora de la durabilidad; e hidrofugantes, de manera que, sin perjudicar la permeabilidad de estos materiales al vapor de agua, se evite la penetración de agua por capilaridad mejorando la durabilidad. Sin embargo, en la mayor parte de los casos, toda la información disponible se circunscribe al efecto de un único aditivo, sin contemplar el posible efecto conjunto o incluso sinérgico de las combinaciones más interesantes de dos o más aditivos y/o adiciones puzolánicas. El estudio de las sinergias entre estos componentes ofrece posibilidades muy interesantes de avance científico-técnico. Precisamente este es el objetivo del trabajo: diseño de nuevos morteros de inyección de cal que puedan ser utilizados para la restauración del Patrimonio Edificado mediante combinación adecuada de aditivos superplastificantes (éteres de policarboxilato, condensados de naftaleno-formaldehído, sulfonato de melamina y ácido poliacrílico), hidrofugante (oleato sódico) y adiciones minerales puzolánicas (microsílice y metacaolín).
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Autores: Pérez Nicolás, María; Navarro Blasco, Íñigo; Fernández Álvarez, José María; et al.Libro: Tradición, versatilidad e innovación en la cal: un material de excelenciaISSN: 978-84-8081-604-5 2018 págs. 268 - 279ResumenDiferentes morteros de cal fueron modificados por la incorporación en masa de aditivos fotocatalíticosnanoestructurados (TiO2 o TiO2 dopado con hierro (Fe-TiO2) o vanadio (V-TiO2)). Las propiedades plásticas y endurecidas de estos morteros han sido evaluadas para estudiar la influencia de estos nanoaditivos. Los retrasos en la demanda de agua observados en las pastas de cal se atribuyeron al impedimento de la difusión de CO2 dentro de la pasta. El TiO2 y el TiO2 dopado no mostraron reactividad puzolánica alguna. El examen por microscopía electrónica de barrido de los morteros de cal mostró que las fases predominantes en la microestructura eran placas hexagonales de portlandita y las aglomeraciones gruesas escalenoédricas de calcita. Se encontró que el Fe-TiO2 se distribuía homogéneamente, mientras que el análisis EDS demostró la tendencia al aglomeramiento del V-TiO2. La capacidad de absorción de agua no se vio afectada por la incorporación de nanoaditivos, lo cual es una característica favorable para la aplicación de estos morteros.
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Autores: Durán Benito, Adrián; González Sánchez, Jesús Fidel; Navarro Blasco, Íñigo; et al.Libro: Tradición, versatilidad e innovación en la cal: un material de excelenciaISSN: 978-84-8081-604-5 2018 págs. 228 - 240ResumenEl presente trabajo tiene como principal objetivo estudiar las interacciones que se producen cuando se adicionan separadamente dos superplastificantes (PNS ¿sulfonato de polinaftaleno- y LS ¿lignosulfonato-) a un conglomerante aéreo (cal aérea Cl 90-S) y a uno hidráulico formado por cal aérea a la que se le ha añadido metacaolín como material puzolánico, y los efectos que dichas adiciones tienen en las propiedades de los sistemas. Para la fabricación de los morteros, se empleó árido calcáreo. Adicionalmente, se efectuaron ensayos de durabilidad en morteros con la composición citada, sometiéndolos a ciclos de hielo-deshielo y a ataque con sulfatos. Aunque se realizaron algunas medidas con las pastas en estado fresco, la mayoría de los experimentos (resistencia a compresión y a flexión, TG-ATD, DRX, FTIR-ATR, porosimetría de intrusión de mercurio) se realizaron tras períodos de fraguado del mortero de 7, 28, 91, 182 y 365 días. Se detectaron fases silicatadas y silicoaluminatadas en los morteros estudiados, a pesar de que las experiencias se realizaron a temperatura ambiente y con un bajo porcentaje de material puzolánico (¿20 %). La presencia de LS impidió el proceso de carbonatación, lo que a su vez provocó un decrecimiento en los valores de resistencia mecánica cuando se trataba de morteros hidráulicos. Se observó asimismo una mayor porosidad y un mayor tamaño medio de poro en el caso de sistemas con LS. La durabilidad (ciclos hielo-deshielo) de los morteros mejoró notable
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Autores: Álvarez Galindo, José Ignacio (Editor); Fernández Álvarez, José María (Editor); Navarro Blasco, Íñigo (Editor); et al.ISSN: 978-84-09-09077-8 2019ResumenThis book collects the abstracts of the communications presented in the 5th Historic Mortars Conference (HMC 2019) organized by the Heritage, Materials & Environment (MIMED) Research Group of the Chemistry Department of the University of Navarra at the School of Sciences in Pamplona from 19 to 21 June 2019.
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Autores: Álvarez Galindo, José Ignacio (Editor); Fernández Álvarez, José María (Editor); Navarro Blasco, Íñigo (Editor); et al.ISSN: 978-2-35158-221-3 2019ResumenProceedings of the 5th Historic Mortars Conference (HMC 2019) held at the University of Navarra in Pamplona from the 19th to the 21st June 2019.
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Autores: Álvarez Galindo, José Ignacio (Editor); Fernández Álvarez, José María (Editor); Navarro Blasco, Íñigo (Editor); et al.ISSN: 978-84-09-02249-6 2018ResumenEl Fórum Ibérico de la Cal, FICAL, es una asociación sin ánimo de lucro cuyo objetivo es el desarrollo de la investigación, la formación y la difusión de la producción y el uso de la cal. Después de las exitosas V Jornadas celebradas en el LNEC de Lisboa, la Universidad de Navarra toma el relevo y organizará en Pamplona, en la Facultad de Ciencias, las VI Jornadas FICAL, del 28 al 30 de mayo de 2018. Estas Jornadas están abiertas a participantes de distintas procedencias e intereses: restauradores, arquitectos y arquitectos técnicos, químicos, geólogos, ingenieros civiles y de materiales, historiadores, científicos, profesionales del sector industrial, estudiantes, empresas productoras¿ con el común denominador de conocer más posibilidades de aplicación, características, comportamiento y aspectos innovadores y tecnológicos en relación con la cal. Se conocen aplicaciones de la cal desde tiempos inmemoriales, particularmente en construcción: morteros, soportes decorativos y pictóricos. La cal es un material íntimamente ligado al Patrimonio Histórico-Artístico y se sigue produciendo a partir de las mismas materias primas. Destacan, entre sus características, la plasticidad de las argamasas que utilizan cal, su capacidad higroscópica y desinfectante, sus propiedades aislantes y su durabilidad. La cal es perfectamente compatible con estructuras antiguas, es idónea para procesos de restauración y rehabilitación, pero también tiene interés en obra nueva porque aporta estabilidad,
Proyectos desde 2018
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Título: Plan de control de calidad de los materiales de construcción con tierraCódigo de expediente: TED2021-129705B-C33Investigador principal: JOSE IGNACIO ALVAREZ GALINDO.Financiador: AGENCIA ESTATAL DE INVESTIGACIONConvocatoria: 2021 AEI Proyectos de Transición Ecológica y DigitalizaciónFecha de inicio: 01-12-2022Fecha fin: 30-11-2024Importe concedido: 126.500,00€Otros fondos: Fondos MRR
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Título: NUEVOS MORTEROS DE CAL CON ADITIVOS Y MATERIALES MICROENCAPSULADOS DE CAMBIO DE FASE PARA MEJORAR LA EFICIENCIA ENERGÉTICA Y CONFORT TÉRMICO DEL PATRIMONIO ARQUITECTÓNICOCódigo de expediente: PID2020-119975RB-I00Investigador principal: JOSE IGNACIO ALVAREZ GALINDO, IÑIGO NAVARRO BLASCO.Financiador: AGENCIA ESTATAL DE INVESTIGACIONConvocatoria: 2020 AEI PROYECTOS I+D+i (incluye Generación del conocimiento y Retos investigación)Fecha de inicio: 01-09-2021Fecha fin: 31-08-2025Importe concedido: 121.000,00€Otros fondos: -
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Título: Ayuda contratacion personal investigador y tecnologico GN2021Código de expediente: 0011-1307-2021-000061Investigador principal: JOSE IGNACIO ALVAREZ GALINDO.Financiador: GOBIERNO DE NAVARRAConvocatoria: 2021 GN Ayudas para la contratación de personal investigador y tecnológicoFecha de inicio: 30-07-2021Fecha fin: 29-07-2022Importe concedido: 20.000,00€Otros fondos: -
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Título: Optimización de nuevos morteros de restauración de cal mediante combinaciones de aditivos y adiciones minerales puzolánicas.Código de expediente: MAT2015-70728-PInvestigador principal: JOSE IGNACIO ALVAREZ GALINDO.Financiador: MINISTERIO DE CIENCIA E INNOVACIÓNConvocatoria: 2015 MINECO EXCELENCIA. PROYECTOS I+DFecha de inicio: 01-01-2016Fecha fin: 31-12-2019Importe concedido: 71.148,00€Otros fondos: -
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Título: Determinaciones de Rayos X, Análisis Termodiferencial y AnálInvestigador principal: JOSE IGNACIO ALVAREZ GALINDOFecha de inicio: 01-01-2020Fecha fin: 31-12-2023Importe: 0Otros fondos: -