An Experimental Study on Water Permeability of Architectural Mortar Using Waste Glass as Fine Aggregate

This paper investigates the water permeability, consistency and density of architectural mortar with various contents of glass sand as fine aggregate. To reduce the effect of alkali-silica-reaction (ASR), metakaolin (MK) was used as supplementary cementitious material (SCM) instead of a component of white cement. The microstructure of glass sand mortar was visualized by means of scanning electron microscope (SEM) images. The experimental results showed that the permeability of the mortar increased with the glass sand, reaching its maximum at about 60–80% glass sand content. The optimum MK content varied with the content of glass sand, and higher content of MK was required for 60% glass sand. In addition, the consistency and density of mortar had a negative correlation with the increase of glass sand.

Preparation and characterisation of photocatalytic pigments for architectural mortar based on ultramarine blue

Architectural mortar is used in the building sector when aesthetic surface value is required and therefore, these surfaces present a great potential to be used as a solution for the reduction of atmospheric pollution. In the present work, an inorganic ultramarine blue pigment has been modified to provide the mortars with colour and photocatalytic properties, simultaneously. To modify the pigment, a sol–gel coating based on titanium n-butoxide precursor has been applied on its surface. The influence of different parameters affecting the coating formation, such as the pH and titanium weight content of the sol–gel reactants, has been studied. Moreover, the formation of a coating on the pigment’s surface with several amounts of TiO2 anatase nanoparticles has also been explored. A pigment with better photocatalytic properties has been obtained at pH = 12 applying a coating based on titanium n-butoxide precursors (Ti precursor/pigment weight ratio = 0.5) with 2 wt.% of titania anatase nanoparticles, maintaining the original pigment colour. Moreover, mortars with the new pigment present higher flexural strength and similar compressive strengths than non-modified mortars ensuring the applicability of the pigment in the building sector.

Cost Optimization of Mortars Containing Different Pigments and Their Freeze-Thaw Resistance Properties

Nowadays, it is common to use colored concrete or mortar in prefabricated concrete and reinforced concrete construction elements. Within the scope of this study, colored mortars were obtained with the addition of brown, yellow, black, and red pigments into the white cement. Those mixtures are examined for their compressive strength, unit weight, water absorption, and freeze-thaw resistance. Subsequent to comparison of these properties, a cost optimization has been conducted in order to compare pigment costs. The outcomes showed that the pore structure in architectural mortar applications plays an important role in terms of durability. And cost optimization results show that light colored minerals can be used instead of white cements.