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Lightweight geopolymers have been researched and used in specific applications due to their differentiated properties and, particularly, due to the lower environmental impacts in their manufacture, mainly associated with the use of raw materials with a low environmental impact and the reduction in greenhouse gas emissions. In this study, light geopolymers, using metakaolin, sodium silicate, sodium hydroxide, and hydrogen peroxide (H2O2), were evaluated. The effects of H2O2 concentration were evaluated up to a concentration of 1% in pastes and mortars. The properties of thermal conductivity, density, compressive strength, and modulus of elasticity were determined. The simulation of the thermal transmittance of cladding panels applied to a facade was also performed. Mortars with a H2O2 concentration of 0.2% obtained a compressive strength of 18 MPa and thermal conductivity of 0.55 W/mK, which was 60% less than the thermal conductivity obtained for the reference composition. The simulation of a panel for use on a facade showed that the thermal resistance increased from 0.27 (m2.K/W) to 0.42 (m2.K/W), indicating the efficiency of the geopolymer for use as a thermal control material.

Preparing a high fluidity paste is a major step in ultra-high performance concrete (UHPC) development with respect to its self-compacting ability as well as its ultra-high strength. In this regard, some experiments have been carried out in order to study various superplasticizer (SP) addition methods and times. Among these procedures, stepwise and delayed methods seem to be more efficient compared to direct addition of SP with or immediately after water addition. However, few studies regarding water addition time and method have been conducted since now. In this research work, the effects of water and SP addition methods on the fluidity of paste were investigated. The results demonstrated that stepwise and delayed water beside delayed SP addition remarkably reduce the flow time. This maximum fluidity was achieved after totally 15 minutes of mixing including 3 minutes after 70% of water addition to powder, as first-part water, 6 minutes after SP addition and finally an extra 6 minutes after second-part water which is 30% of the total water. Based on this procedure, the opportunity for developing self-compacting and durable UHPC could be accessible. Furthermore, using higher content of aggregates and supplementary cementitious materials would be possible due to higher fluidity of the paste which finally results in an eco-efficient UHPC.

Is there any law related to sustainable buildings and eco-efficient solutions in Spain? How harmful effects on the environment caused by the building industry are regulated? The emergence of concepts such as sustainability or eco-efficiency in the mid-twentieth century has caused a deep impact in the building industry, changing traditional techniques, systems and procedures that have promoted research for the use of materials more efficient. All aimed at lessening the harmful effects on the environment. In order to have a better comprehension of the impact caused by the regulation in the construction model we have prepared a comprehensive inventory of the existing regulations in Europe, Spain and Andalusia on sustainable buildings and ecoefficient solutions. All of this allows us to shape the current legal framework and its impact on the eco-efficient building model with the prospect of advancing in the achievement of sustainability objectives and therefore it is crucial to have a fair regulation on this field, adapted to the progress and in the same line with the sustainability objectives established in the European framework ¿Existen normas vinculadas a la construcción sostenible y las soluciones ecoeficientes en España? ¿Cómo se regulan los efectos perjudiciales sobre el medio ambiente provocados por el sector de la construcción? La aparición de los conceptos de sostenibilidad y eco-eficiencia a mediados del siglo XX ha supuesto la modificación de hábitos dentro del ámbito de la construcción, regenerando técnicas constructivas, sistemas constructivos y procedimientos que han fomentado la investigación para el uso de materiales más eficientes. Todo ello orientado a aminorar los efectos perjudiciales sobre el medio ambiente. A efectos de una mejor comprensión del impacto normativo en el modelo constructivo hemos elaborado un detallado inventario de las normas aplicables en Europa, España y en Andalucía relativas a las construcciones sostenibles y las soluciones eco-eficientes. Todo ello nos permite perfilar el actual marco normativo y su impacto en modelo constructivo actual de construcciones sostenibles y soluciones Eco-Eficientes, ante la perspectiva de avanzar en la consecución de objetivos de sostenibilidad para lo cual es necesario contar con una regulación legal justa de esta materia, adaptada a los avances y en efectiva consonancia con los planteamientos de sostenibilidad que se establecen en el marco europeo

One of the main climate trigger are CO2 emissions. In the field of architecture and construction, one of the most harmful materials is the cement due to its employment and its polluting power (about 5 and 8% of the worldwide CO2 emissions). Thus, the search of an alternative material is essential. This paper shows the possibility of using eco-efficient mortars as structural materials, in order to guarantee both safety and environment preservation in the strengthening/refurbishment/retrofitting of structures. In those mortars, the binder can be substituted by organic or inorganic materials (e.g. fly ash, ground granulated blast furnace slag, rice husk ash, palm oil fuel ash). From this strategy, the waste reduction is promoted, as wastes are immobilised without polluting the environment essential. Thus, it is encouraged the re-use of architecture which is an essential factor to get a more sustainable habitat. The obtained results allow setting a guide that makes easier the selection of eco-efficient mortars (guaranteeing both structural safety and environment preservation) to the agents involved in processes of structural works. Uno de los principales detonantes del cambio climático son las emisiones de CO2. En el ámbito de la arquitectura y la construcción, uno de los materiales más perjudiciales en relación a su uso y su poder contaminante es el cemento (entre el 5 y 8% de las emisiones de CO2 en el mundo son generadas por éste). Por tanto, es fundamental buscar alternativas a su uso. Esta investigación muestra la posibilidad del uso de morteros eco-eficientes como materiales estructurales que garanticen tanto la seguridad de la construcción como la preservación del medioambiente en intervenciones de refuerzo/ rehabilitación/consolidación estructural. En estos morteros, el conglomerante o bien es un material distinto al cemento o se realiza la sustitución de parte de éste por materiales orgánicos o inorgánicos como cenizas volantes, residuos de altos hornos, cáscaras de arroz, cenizas de aceite de palma, entre otros, con lo que también se propiciaría la reducción de residuos que pasarían a inmovilizarse sin contaminar la naturaleza. Así, se fomenta el reciclaje de la arquitectura, siendo éste un factor clave para un hábitat sostenible. Los resultados obtenidos permiten establecer una guía que facilite a los agentes implicados en las actuaciones de intervención estructural la selección de morteros eco-eficientes óptimos, tanto para garantizar la seguridad como para preservar el medioambiente.

Producción Científica One of the main climate trigger are CO2 emissions. In the field of architecture and construction, one of the most harmful materials is the cement due to its employment and its polluting power (about 5 and 8% of the worldwide CO2 emissions). Thus, the search of an alternative material is essential. This paper shows the possibility of using eco-efficient mortars as structural materials, in order to guarantee both safety and environment preservation in the strengthening / refurbishment / retrofitting of structures. In those mortars, the binder can be substituted by organic or inorganic materials (e.g. fly ash, ground granulated blast furnace slag, rice husk ash, palm oil fuel ash). From this strategy, the waste reduction is promoted, as wastes are immobilised without polluting the environment essential. Thus, it is encouraged the re-use of architecture which is an essential factor to get a more sustainable habitat. The obtained results allow setting a guide that makes easier the selection of eco-efficient mortars (guaranteeing both structural safety and environment preservation) to the agents involved in processes of structural works. Uno de los principales detonantes del cambio climático son las emisiones de CO2. En el ámbito de la arquitectura y la construcción, uno de los materiales más perjudiciales en relación a su uso y su poder contaminante es el cemento (entre el 5 y 8% de las emisiones de CO2 en el mundo son generadas por éste). Por tanto, es fundamental buscar alternativas a su uso. Esta investigación muestra la posibilidad del uso de morteros eco-eficientes como materiales estructurales que garanticen tanto la seguridad de la construcción como la preservación del medioambiente en intervenciones de refuerzo/ rehabilitación/consolidación estructural. En estos morteros, el conglomerante o bien es un material distinto al cemento o se realiza la sustitución de parte de éste por materiales orgánicos o inorgánicos como cenizas volantes, residuos de altos hornos, cáscaras de arroz, cenizas de aceite de palma, entre otros, con lo que también se propiciaría la reducción de residuos que pasarían a inmovilizarse sin contaminar la naturaleza. Así, se fomenta el reciclaje de la arquitectura, siendo éste un factor clave para un hábitat sostenible. Los resultados obtenidos permiten establecer una guía que facilite a los agentes implicados en las actuaciones de intervención estructural la selección de morteros eco-eficientes óptimos, tanto para garantizar la seguridad como para preservar el medioambiente.

The main research goal is proving the possibility of using eco-efficient mortars as structural materials, to guarantee both safety and environment preservation in the strengthening/refurbishment/retrofitting of structures. After a comprehensive review on ecoefficient mortars, mechanical properties, rheological behaviour, setting times, durability, and environmental impact (GWP and EE) were analysed. Thus, a qualitative comparison between result obtained and OPC reference cement mortar was possible. Research is completed with an experimental characterisation of ashes, and mechanical test of mortar/concrete samples with plant biomass ashes. The research aims to demonstrate the feasibility and potential of plant biomass ashes in cement-based building materials. The performance from those mortars must be studied with static and dynamic loads as well as the resulting CO2 emission reduction. Finally, this research will propose a protocol selection of eco-efficient mortars based on an analytical hierarchy process (AHP)-based assessment method. Resumen: capacidades mecánicas suficientes para ser usados en refuerzos estructurales y que den resultados aceptables desde un punto de vista mecánico, económico y medioambiental. Tras realizar una exhaustiva revisión bibliográfica , se analizan las propiedades mecánicas, el comportamiento reológico, tiempo de fraguado, durabilidad e impacto medioambiental (GWP y EE), lo que permite realizar una comparativa cualitativa entre los resultados obtenidos y el mortero de cemento Portland de referencia. La investigación se completa con ensayos mecánicos realizados a morteros de cemento con sustitutivos de cenizas de biomasa vegetal obtenidas de plantas de producción de energía, las cuales han sido previamente caracterizadas. Con el desarrollo de la investigación se espera demostrar la viabilidad del uso de cenizas de biomasa vegetal como sustitutivo parcial del cemento con valores de resistencias suficientes, analizando el desempeño de estos morteros eco-eficientes desde la seguridad estructural, bajo cargas estáticas y dinámicas, acompañado del análisis de beneficios medioambientales para la reducción de las emisiones de CO2. Como objetivo final, se espera concluir con la elaboración de un protocolo de selección de dichos morteros eco-eficientes empleando el método de jerarquías analíticas (AHP).