Impact of incorporating recycled glass on the photocatalytic capacity of paving concrete blocks

This paper presents the results of the development of translucent photocatalytic mortar produced with incorporation of recycled glass, applied on the superficial layer of concrete blocks intended for urban paving. The main aim of developing the translucent mortar was to enhance the photocatalytic capacity in double-cap concrete blocks. The incorporation of glass in the mortar was performed by replacing the mineral aggregate at percentages ranging from 20 to 61%. The recycled glass used in the research was submitted to decontamination process, being then crushed and sieved into the desired fractions. The effects on the simple compression strength due to the incorporation of recycled glass were evaluated, as well as the translucency of the photocatalytic layer. Based on the strength and translucency results obtained, the highest percentage of glass incorporation to the mortar was defined. As final criterion for the validation of this optimized percentage, the alkali-silica reactivity test (ASR) was performed. Lastly a laboratorial comparison was performed to evaluate the NOx degradation efficiency of blocks with and without recycled glass incorporation to the mortar surface under different environmental conditions. The results show that the incorporation of glass in an optimized percentage is feasible for mortar production, since satisfactory compression strength and translucency were obtained, without alkali-silica reactivity, providing increase in photocatalytic efficiency. (C) 2020 Elsevier Ltd. All rights reserved.