Experimental investigation of eco-friendly concrete utilising waste glass

Concrete is one of the main structural materials used in the world; hence, improvement of the concrete mix design with respect to variable issues and requirements is of great importance. Moreover, environmental issues and waste materials have become major concerns these days. In this study, to move towards a more sustainable and ecofriendly construction industry, recycled waste glasses were used as partial replacement for sand and gravel aggregates in concrete. Simultaneously, the effects of silica fume as cement replacement and property enhancer in the eco-friendly concrete mix were investigated. The results of the conducted experiments indicated that utilisation of glass aggregates in general results in strength reduction. However, at proportions of 40% glass replacing aggregates and 5% microsilica replacing cement, no strength reduction was observed compared with normal concrete. An increase in the substitution of natural aggregates with glass reduced the total water absorption: at a proportion of 60% aggregate replaced by glass, the water absorption was reduced by 74%. On the other hand, with the replacement of 10% of cement with microsilica, water absorption decreased up to 17%. The results also indicated that an increase in the dosage of glass to 60% decreased the volume of permeable pore space by 70%.