Page 23 - New Trends in Green Construction

DURABILITY OF CEMENT MORTARS WITH ARCHITECTURAL RESIDUES INSULATED FROM MINERAL WOOL
Carolina Piña Ramírez, Mercedes del Río Merino, Alejandra Vidales Barriguete
Keywords: Cement mortars, mineral fibres, recycling, durability, construction and demolition waste 1. Introduction
Mineral wool is currently the most used insulation in the European Union, and the quantities of this waste have increased alarmingly in the last decade (Papadopoulos 2005), making it essential to recycle or reuse the material, which is not current practice.
This study is part of a research that analyses the viability of the mineral wool from the construction and demolition waste (CDW) as reinforcement of cement matrixes. The objective is to analyze the durability of a material composed of a cement mortar matrix to which the aforementioned waste is incorporated.
2. Materials and methods
The materials used in this study are Portland cement Cem II/B-L 32,5 N (supplied by the company Cementos Portland Valderrivas, Madrid, Spain), river sand of 4 mm sieve diameter, and three types of mineral wool waste: fiberglass, rockwool, and mixed mineral wool waste.
The three types of mineral fiber waste underwent a pretreatment in this study: they were crushed in a machine of 550W power at 50 Hz, for three intervals of 3 min each, putting them into a suitable form for incorporation into the mortars. A series of test samples were made with the three types of fiber waste, adding them to replace a 50% of the river sand measured by volume. According to the bibliography reviewed and previous tests the dosage for all samples was 1:3:0.6 (cement:sand:water).
As mortars that incorporate 50% of fibers are more porous (Piña et al. 2018), they may also present problems of durability. Therefore, if these compounds can guarantee their durability, they can also be used for those with a lower percentage of residue.
For this purpose, an experimental plan is made in which cement mortar specimens are made with 50% of different types of mineral wool waste, on which freezing, crystallization of salts, determination of water vapor permeability of hardened mortar, and resistance to adhesion tests are carried out, to evaluate their viability as a reinforcement material (López-Buendía et al. 2013).
3. Results and conclusions
Regarding the frost resistance test of mortars, the results of losses of flexural and compressive strength are not significant when comparing mortars with additives to reference mortars. A visual inspection was also carried out after the cycles of ice and thaw, with no significant deterioration in the surface of the specimens. For all these reasons, the mortars made in the present investigation can be considered as non-frozen.
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New Trends in Green Construction