Impact of combined use of ground glass powder and crushed glass aggregate on selected properties of Portland cement concrete

• Impact of using large volume of recycled glass in concrete on its properties was evaluated.
• Performance of concrete with glass aggregate was compared to concrete with natural aggregate.
• Use of granular glass aggregate versus fine glass powder on properties of concrete was evaluated.
• Using combination of glass aggregate with glass powder produces strong and durable concrete.

In this study, the impact of using ground glass powder as either a cement replacement material or as an aggregate replacement material on the fresh and mechanical properties of Portland cement concrete were investigated. Also, the synergistic influence of using combinations of glass powder with crushed glass aggregate or natural mineral aggregate on the properties of concrete were investigated. The properties of concrete evaluated in this study include slump (workability), density, air content, compressive and splitting tensile strengths of concrete.Results from this investigation showed that the workability of concrete was significantly affected depending on whether the glass powder was used as cement or aggregate replacement material, however, air content and density of concrete were affected only when glass powder was used as cement replacement material. In terms of mechanical properties, in the absence of glass powder in concrete, the compressive and splitting tensile strength values of the concrete specimens containing crushed glass aggregate were significantly lower than that of the concrete containing natural mineral aggregate. When glass powder was used as a cement replacement material in concrete, the compressive strength of concrete decreased regardless of the aggregate type. However, when glass powder was used as an aggregate replacement material, the compressive strength of concrete depended on the type containing crushed glass aggregate increased while the compressive strength of concrete containing natural mineral aggregate decreased.