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Circular Economy
procedure defined in ASTM D7984 (2016, 2016). In the second phase, it was determined by the heat flow methodology defined in UNE-EN 12667 (2002).
3. Results and conclusions
The coefficient of thermal conductivity, λ, resulted from both methodologies, is similar in the compounds with PR and in the reference. It differs 25%, in the first experiment with the generic value assigned to the high hardness plaster (900- 1200kg/m3) in the Technical Building Code (0.43 W/mK) and 40-50% in the second experiment.
After comparison of the outcome values from the different mixtures, it is observed that thermal conductivity coefficient does not follow an increasing or decreasing relationship: the results are random even with an increase of the quantity of PR
In general terms, the thermal conductivity coefficient depends on the density: it is observed that the increase in the number of pores do not reduces the thermal conductivity (Villanueva & García Santos, 2001). However, the study of these compounds this property is not fulfilled by not observing an increasing or decreasing relationship between the two variables.
Although significant results were not achieved in terms of reduction of the thermal conductivity coefficient, the fact that it remains stable is also interesting.
Therefore, it could be considered that the material studied presents an interesting option to increase sustainability in the construction process:
• On one hand, the use of natural resources is reduced: the higher the percentage of residue is used in the mixture, the less amount of gypsum and water is needed;
• On the other hand, the amount of plastic waste is minimized by applying circular economy criteria. Hence, the plastic waste becomes a resource.
4. References
UNE-EN 13279-2:2014 "Yesos de construcción y conglomerantes a base de yeso para la construcción. Parte 2: Métodos de ensayo", UNE-EN 13279-2 C.F.R. (2014).
UNE-EN 12667 "Materiales de construcción. Determinación de la resistencia térmica por el método de la placa caliente guardada y el método del medidor de flujo de calor. Productos de alta y media resistencia térmica", UNE-EN 12667 C.F.R.
ASTM D7984 "Standard Test Method for Measurement of Thermal Effusivity of Fabrics Using a Modified Transient Plane Source (MTPS) Instrument", ASTM D7984 C.F.R. (2016).
Barriguete, A. V., del Río Merino, M., Sánchez, E. A., Ramírez, C. P., & Arrebola, C. V. (2018). Analysis of the feasibility of the use of CDW as a low-environmental-impact aggregate in conglomerates. Construction and Building Materials, 178, 83-91.
del Río Merino, M., Garcia Navarro, J., & Villoria Saez, P. (2011). Legal aspects which implement good practice measures in the management of construction and demolition waste. Open Construction & Building Technology Journal, 5(Suplem), 7.
Gómez-Zamorano, L., Iñiguez-Sánchez, C., & Lothenbach, B. (2015). Microestructura y propiedades mecánicas de cementos compuestos: Efecto de la reactividad de adiciones puzolánicas e hidráulicas. Revista ALCONPAT, 5(1), 18-30.
Jiménez Rivero, A., Guzmán Báez, A. d., Garcia Navarro, J., & González Cortina, M. (2011). Nuevos Materiales de Base Yeso con Incorporación de Residuos de Caucho: Caracterización Físico-Mecánica.
San-Antonio González, A., Río Merino, M. D., & Viñas Arrebola, C. (2013). Estado de la cuestión sobre compuestos de yeso. la importancia actual de los residuos. Paper presented at the Congreso Internacional de Construcción Sostenible y Soluciones Ecoeficientes (1o. 2013. Sevilla).
Villanueva, L. d., & García Santos, A. (2001). Manual del yeso.
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