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This paper analyses the influence of the fine fraction of two types of construction and 5 demolition waste (CDW1 and CDW2) on the properties of recycled aggregates (RA) and 6 masonry mortars. The CDW1's main component was ceramic while the CDW2 were 7 concrete. Three different kinds of fine RA were produced from each source of CDW; the 8 first type was produced by only using the fraction finer than 4.76 mm, the second one by 9 employing only the coarser fraction than 4.76 mm, and the third type was a mix of both 10 fractions of CDW. The masonry mortars were produced employing the 100% substitution 11 of natural aggregates. The results show that all the recycled mortars achieved a higher 12 water retentivity capacity than that of the conventional mortars. However, the sole use of 13 the fine fraction of the CDW was found to have a deleterious effect over the hardened 14 mortar properties, thus making it only adequate for the rendering or bonding of interior 15 walls at or above ground level. In contrast a combination of both the fine fraction and 16 coarse fraction of the CDW in the production of the RA achieved all the minimum 17 requirements for rendering and bonding masonry mortar. 18 Highlights 20  Two sources of CDW, one with ceramic and other with concrete as main components, 21 were employed. 22  Three different RA were obtained from two different sources of CDW. 23  Masonry mortars employing 100% of recycled aggregate were validated. 24  Ceramic high content recycled aggregates mortars achieved the most adequate 25 properties. 26  The employment of the coarse fraction of the CDW guarantee high quality aggregates 27 for masonry mortar. 28

Infrared thermography is an evaluation technique that helps to identify anomalies and can provide information on their incidence and severity. The aim of this study is to apply quantitative thermography to study a case of severe cracks in facade analyzing the evolution of temperatures and Delta-T. The temperature evolution was studied over a day. There was sun incidence occurring during part of the day, allowing to calculate and assess the evolution of the associated temperatures. Thermograms were acquired hourly during the study period. The highest temperatures were observed at 12:00 noon, and the larger Delta-T between 10:00 and 12:00. There were differences between the Delta-T profiles among the three regions studied. The best time for analysis is when Delta-T is higher. Cracks with higher Delta-T were considered more degraded, and generalized branched cracks did not allow a comparative conclusion.

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This paper details the research work carried out on masonry mortars produced employing recycled aggregates in 100% substitution for natural sand aggregates. The main objective of the work being the validation of the resulting recycled aggregate mortar for use as a new construction material in Cuba. The recycled aggregates were acquired from the crushing of demolition material obtained from four different houses of distinct construction types. The work was carried out in two experimental stages. In stage 1, mortars with different percentages of recycled aggregates were produced and analysed. The analysis was carried out in order to achieve the optimal mix dosage, while employing the largest usable volume of recycled aggregates and in compliance with the functional requirements established by Cuban regulations. In stage 2, all mortars were produced employing the defined optimal mix proportion The fresh state properties (water retentivity) and hardened state (flexural, compression and bond strengths and capillary absorption capacity) were evaluated in the mortars produced with the other three mixed recycled aggregates of different compositions. It was concluded that the mortars produced with recycled aggregates needed less filler than that of the control mortar in order to obtain adequate properties in their fresh state. However, these recycled aggregate mortars obtained lower mechanical properties and higher capillary absorption that those of the control mortar. Nevertheless they were in compliance with the minimum requirements established in the Cuban regulation.Keywords: construction and demolition waste, recycled fine aggregate, masonry mortars, properties in fresh and hardened state Resumen En el presente trabajo se detalla la investigación llevada a cabo sobre morteros de albañilería utilizando áridos reciclados en sustitución al 100% de la arena natural. El objetivo principal del trabajo es la validación del mortero fabricado con árido reciclado como nuevo material de construcción en Cuba. Los áridos reciclados fueron obtenidos de la trituración del material de demolición de cuatro tipos de viviendas de diferente tipología de construcción. El trabajo se llevó a cabo en dos etapas experimentales. En la etapa 1, se fabricaron y analizaron morteros fabricados con diferentes porcentajes de un tipo de árido reciclado. El análisis se llevó a cabo con el fin de obtener la dosificación óptima del mortero utilizando el mayor porcentaje de árido reciclado posible y en cumplimiento con los requerimientos establecidos por las normas cubanas. En la etapa 2, todos los morteros se fabricaron utilizando la óptima dosificación definida en la etapa anterior. En cada mortero fabricado con los otros tres tipos de áridos reciclados obtenidos, se determinó la retención de agua en estado fresco, y las propiedades de resistencia a flexión, compresión y adherencia así como la absorción capilar en estado endurecido. Se concluyó que los morteros producidos con árido reciclados necesitan menos filler que el de mortero de contro...

Resumen En el presente trabajo se determina cómo ocurre el transporte de agua, en el sistema mortero/bloque, con el objetivo de vincular el comportamiento de la resistencia a la adherencia por tracción perpendicular, con el transporte de agua y la porosidad del substrato. Para ello fueron fabricados dos morteros con áridos de diferentes granulometrías, a los cuales se le determinó sus propiedades en estado fresco y en estado endurecido. Se determinó la cantidad de agua transportada, a partir de mediciones de humedad con sensores resistivos, en diferentes camadas de los morteros aplicados sobre sustrato de hormigón y sustrato cerámico. Los bloques de albañilería usados como sustrato, fueron caracterizados atendiendo a sus propiedades físicas, relacionadas con la absorción de agua y la porosidad. Los resultados mostraron que existe una relación directa entre el porciento de agua transportada en las diferentes camadas, con la resistencia a la adherencia del mortero. Comprobándose además, la no existencia de relación entre los ensayos de retención de agua del mortero y el total de agua transportada en el sistema mortero/bloque.

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