Abstract

Recycling is an important habit to avoid waste. This paper evaluates the performance of masonry mortar, elaborated by replacing natural sand with recycled fine aggregate (RFA) obtained from mortar. Five families of mixtures were prepared with different replacement proportions: 20%, 40%, 60%, and 100%. A 1:4 volumetric cement-to-aggregate ratio was used for all mixtures by experimentally adjusting the amount of water to achieve the same consistency of 175 ± 5 mm. The effects of the following procedures were analyzed: (1) the use of a deconstruction technique to collect the RFA, (2) pre-wetting of the aggregates, and (3) the use of a commercial plasticizer. Experimental results show that it is possible to use this type of recycled fine aggregate as a substitute for natural sand by up to 60% in the manufacture of masonry mortar without significantly affecting its properties.

Abstract

Abstract

The most commonly used wall coverings are still, undoubtedly, plasters and renders, whether lime-based or cement-based, whether traditional and prepared in-situ or pre-dosed. In accordance with the available standards, the characterization of these mortars is made on laboratory test specimens, with dimensions, curing conditions and test procedures according to the prescribed. However, when applying these mortars to the real substrates, their behaviour will not be the same. After application of the mortar to the substrate, an interface will be formed, and the interactions that occur after the contact of the mortar, still in the plastic state, with the substrate will change over time due to the hydration kinetics and absorption of the substrate. It is very important to know the real behaviour of mortars after application, in order to ensure their durability. A research project is being developed to analyse the proper behaviour of mortars after application to the substrates. In order to characterize a mortar after application to a substrate, it is necessary to detach it. The introduction of a fiberglass grid in the mortarsubstrate interface makes the detachment easier. The purpose of this study is to determine if the placement of this grid will influence the characteristics of the applied mortar. For this, an experimental campaign was carried out, comparing the characteristics of two mortar formulations, applied to different types of substrate (without introduction of the fiberglass grid), with the characteristics of these mortars applied to the same substrates, but with the introduction of a fiberglass grid at the interface mortar-substrate. In this paper, we present the results obtained for some of the physical and mechanical characteristics of cement and hydraulic lime mortars.

Abstract