Utilización de árido reciclado en morteros de albañilería

Abstract

The construction sector is one of the most important economic sectors in the European Union due to its contribution to the generation of wealth and employment. However, it consumes approximately half of all natural resources and generates almost one third of all waste, and this has a major impact on the environment. This sector, therefore, is a key factor in the EU’s transition to a circular economy, in which resources maintain their value for longer and waste generation is minimised in order to achieve a sustainable, hypocarbonic, resource-efficient and competitive economy. The use of recycled aggregates obtained from the treated mineral fraction of construction and demolition waste as a replacement for natural aggregates can reduce the consumption of natural resources and the corresponding environmental impact, since it reduces landfill disposal and maintains the value of resources for longer in the economy. However, recycled aggregate is seldom used due to lack of confidence in its quality, lack of specific standards, or the low price of natural aggregate. In addition, the nature and composition of recycled aggregate (waste of concrete, ceramic, mortar, etc.) together with its impurity content, give the aggregate higher density and water absorption capacity compared to natural aggregate. This latter limitation is increased in the fine fraction of recycled aggregate, which has very limited use in applications subject to high technical requirements. Therefore, applications that do not limit the use of fine recycled aggregate, such as masonry mortars, must be found. Preliminary studies have shown that the greater amount of water needed to improve the consistency of mortar containing recycled fine aggregate, due its higher water absorption capacity, is detrimental to its compressive strength. This is why, the incorporation of 50% recycled fine aggregate does not usually give satisfactory results. Furthermore, we found no evidence of studies that analyse the use of recycled fine aggregate in mortar in terms of the life cycle assessment of the product. Therefore, the main aim of this study has been to evaluate the use of recycled fine aggregate obtained from the treated mineral fraction of C&DW in the manufacture of masonry mortars from the technical and environmental perspective. After testing different dosages, according to standard EN 998-2, in which natural fine aggregate was replaced with different percentages of recycled fine aggregate (25%, 50%, 75% and 100%), the total water/cement ratio of the mortar, and the amount of air-entraining plasticizer admixture, we found that the recycled fine aggregate studied is suitable for the manufacture of general purpose masonry mortar (G), class M5 (> 5 N/mm2) with a plastic consistency of ≥140 mm. Up to 50% of natural fine aggregate can be replaced with recycled fine aggregate without the need to increase the water content of the mortar, and up to 100% if pre-soaked recycled fine aggregate is used. From the environmental perspective, the life cycle assessment carried out in accordance with the ISO 14040 and ISO 14044 standards has shown that the use of recycled fine aggregate reduces the environmental impact associated with masonry mortars by eliminating the need to transport and dispose of the construction and demolition waste in landfills. Environmental impacts are reduced by up to 94% in the Land Use category and by 3.3% in PM2.5 eq emissions. In addition, replacing natural fine aggregate with recycled fine aggregate reduces the extraction and consumption of natural resources and maximises resource efficiency. This makes it possible to increase the recycling rate of construction and demolition waste while maintaining its value, which in turn helps close the loop in the framework of a circular economy. BIBLIOGRAFÍA ANEFA, 2017. Revista Anual 2016/2017 [WWW Document]. Asoc. Nac. Empres. Fabr. áridos en España. URL http://www.aridos.org/ (acceso 11.07.18). Barbudo, A., Galvín, A.P., Agrela, F., Ayuso, J., Jiménez, J.R., 2012. Correlation analysis between sulphate content and leaching of sulphates in recycled aggregates from construction and demolition wastes. Waste Manag. 32, 1229–1235. doi:10.1016/j.wasman.2012.02.005 Bovea, M.D., Powell, J.C., 2016. Developments in life cycle assessment applied to evaluate the environmental performance of construction and demolition wastes. Waste Manag. 50, 151–172. doi:10.1016/j.wasman.2016.01.036 Calvo, N., Varela-candamio, L., Novo-corti, I., 2014. A Dynamic Model for Construction and Demolition (C&D) Waste Management in Spain: Driving Policies Based on Economic Incentives and Tax Penalties 416–435. doi:10.3390/su6010416 Carpio, M., Roldán-Fontana, J., Pacheco-Torres, R., Ordóñez, J., 2016. Construction waste estimation depending on urban planning options in the design stage of residential buildings. Constr. Build. Mater. 113, 561–570. doi:10.1016/j.conbuildmat.2016.03.061 CEN, 2012. Norma Europea EN 998-2. Especificaciones de los morteros para albañilería. Parte 2: Morteros para albañilería. Comité Europeo de Normalización, Bruselas. CEN, 2002. Norma Europea EN 13139. Áridos para morteros. Comité Europeo de Normalización, Bruselas. Comisión Europea, 2016. The European construction sector. A global partner [WWW Document]. URL http://ec.europa.eu/growth/sectors/construction/index_en.htm (acceso 10.09.18). Comisión Europea, 2015. Cerrar el círculo: un plan de acción de la UE para la economía circular, COM (2015) 614 final. Comunicación de la Comisión al Parlamento Europeo, al Consejo, al Comité Económico y Social Europeo y al Comité de las Regiones, Bruselas, 2.12.2015. Comisión Europea, 2014. Oportunidades para un uso más eficiente de los recursos en el sector de la construcción, COM (2014) 445 final. Comunicación de la Comisión al Parlamento Europeo, al Consejo, al Comité Económico y Social Europeo y al Comité de las Regiones, Bruselas, 1.07.2014. Corinaldesi, V., Moriconi, G., 2009. Behaviour of cementitious mortars containing different kinds of recycled aggregate. Constr. Build. Mater. 23, 289–294. doi:10.1016/j.conbuildmat.2007.12.006 Debieb, F., Kenai, S., 2008. The use of coarse and fine crushed bricks as aggregate in concrete. Constr. Build. Mater. 22, 886–893. doi:10.1016/j.conbuildmat.2006.12.013 Eurostat, 2018a. Generation of waste by waste category, hazardousness and NACE Rev. 2 activity in 2016. [env_wasgen] [WWW Document]. Stat. Off. Eur. Communities. URL http://appsso.eurostat.ec.europa.eu/nui/show.do?lang=en&dataset=env_wasgen (acceso 15.11.18). Eurostat, 2018b. Recovery rate of Construction and demolition mineral waste (2016). Composition [WWW Document]. Stat. Off. Eur. Communities. URL https://ec.europa.eu/eurostat/tgm/table.do?tab=table&init=1&plugin=1&language=en&pcode=cei_wm040 (acceso 27.09.18). Eurostat, 2018c. Contribution of recycled materials to raw materials demand (2016) [WWW Document]. Stat. Off. Eur. Communities. URL http://ec.europa.eu/eurostat/tgm/table.do?tab=table&init=1&plugin=1&language=en&pcode=cei_srm010 (acceso 17.04.18). Evangelista, L., de Brito, J., 2007. Mechanical behaviour of concrete made with fine recycled concrete aggregates. Cem. Concr. Compos. 29, 397–401. doi:10.1016/j.cemconcomp.2006.12.004 ISO, 2006a. ISO 14040. Gestión ambiental. Análisis de ciclo de vida. Principios y marco de referencia. International Organization for Standardization, Geneva, Switzerland. doi:10.1520/E0872-82R13.2 ISO, 2006b. ISO 14044. Gestión ambiental. Análisis de ciclo de vida. Requisitos y directrices. International Organization for Standardization, Geneva, Switzerland. doi:10.1520/E0872-82R13.2 Jefatura del Estado, 2011. Ley 22/2011, de 28 de julio, de residuos y suelos contaminados, Boletín Oficial del Estado Num. 181 de 29 de julio, Sec. I. Boletín Oficial del Estado Num. 181 de 29 de julio de 2011, Sec. I, 85650-85705, España. Jiménez, J.R., Ayuso, J., López, M., Fernández, J.M., De Brito, J., 2013. Use of fine recycled aggregates from ceramic waste in masonry mortar manufacturing. Constr. Build. Mater. 40, 679–690. doi:10.1016/j.conbuildmat.2012.11.036 Martín-Morales, M., Zamorano, M., Valverde-Palacios, I., Cuenca-Moyano, G.M., Sánchez-Roldán, Z., 2013. Quality control of recycled aggregates (RAs) from construction and demolition waste (C&DW), in: Pacheco-Torgal, F., Tam, V.W.Y., Labrincha, J.A., Ding, Y., De brito, J. (Eds.), Handbook of Recycled Concrete and Demolition Waste. Woodhead Publishing Limited, pp. 270–303. doi:10.1533/9780857096906.2.270 Ministerio de la Presidencia, 2008. Real Decreto 105/2008, de 1 de febrero, por el que se regula la producción y gestión de los residuos de construcción y demolición. Boletín Oficial del Estado núm. 38, de 13 de febrero de 2008, 7724-7730, España. Parlamento Europeo y Consejo de la Unión Europea, 2018. Directiva 2018/851 del Parlamento Europeo y del Consejo de 30 de mayo de 2018 por la que se modifica la Directiva 2008/98/CE sobre los residuos. Diario Oficial de la Unión Europea, 14.06.2018, L 150, 109-140. Parlamento Europeo y Consejo de la Unión Europea, 2008. Directiva 2008/98/CE de 19 de noviembre de 2008 sobre los residuos y por la que se derogan determinadas Directivas. Diario Oficial de la Unión Europea, 22.11.2008, L 312, 3-30. Rodríguez, G., Medina, C., Alegre, F.J., Asensio, E., Sánchez de Rojas, M.I., 2015. Assessment of Construction and Demolition Waste plant management in Spain: In pursuit of sustainability and eco-efficiency. J. Clean. Prod. 90, 16–24. doi:10.1016/j.jclepro.2014.11.067 UEPG, 2017. A Sustainable Industry for a Sustainable Europe. Annual Review 2016-2017. [WWW Document]. URL http://www.uepg.eu/publications/annual-reviews (acceso 11.07.18). Vegas, I., Azkarate, I., Juarrero, a, Frías, M., 2009. Diseño y prestaciones de morteros de albañilería elaborados con áridos reciclados prodedentes de escombro de hormigón. Des. Perform. Mason. mortars made with Recycl. Concr. aggregates. 59, 5–18. doi:10.3989/mc.2009.44207