Application of waste glass in translucent and photocatalytic concrete

Container glass aggregates and glass powder are waste products of the glass recycling industry. In this research, these products are incorporated in self-compacting concrete (SCC) mixtures, replacing conventional aggregates and fine powders. The SCC mixtures were designed using a particle packing optimization algorithm in order to obtain good properties in both fresh and hardened states. Different mixtures were tested for their strength, alkali-silica reaction (ASR), translucency to the visible light and photocatalytic oxidation (PCO) properties. Results show that the strength of the SCC mixtures containing the waste glass, compared to a reference mixture prepared with conventional aggregates and sand, is slightly lower in all the investigated mixtures. With respect to ASR test results, mixtures with glass aggregates can be classified as highly reactive, but the glass powder can suppress the ASR. Transparency of the prepared concrete plates with glass aggregates is low. The addition of a photocatalyst was studied, to render the material self-cleaning and to promote photocatalytic oxidation (PCO) of NOx. The PCO test results show an improvement of the NOx degradation up to 40% compared to the reference samples without glass particles.