Cleaner production of concrete by using industrial by-products as fine aggregate: A sustainable solution to excessive river sand mining

Abstract

River sand is commonly used as a fine aggregate in concrete. Due to the restriction for the use of river sand in several parts of the world to protect river beds, the demand for alternative fine aggregates is significantly increased in the construction sector. On the other hand, the disposal of industrial by-products is a major concern because of stringent environmental regulations. Use of industrial by-products as an alternative fine aggregate in the concrete is a sustainable common solution to the excessive river mining and disposal of industrial by-products. Although earlier studies on alternative fine aggregates are available, a comprehensive review with a consideration of several industrial by-products is highly limited. Therefore, the potential reuse of fifteen industrial by-products as fine aggregate is presented in this review. Influence of characteristics of alternative fine aggregates on properties of concrete such as workability, compressive strength, water absorption, carbonation, abrasion resistance, chloride permeability, sorptivity, ultrasonic pulse velocity, and drying shrinkage are critically reviewed and compared. From the detailed review, the optimum replacement level of 20% is witnessed for steel slag, copper slag and granite dust aggregates whereas 40% is the optimum replacement level for bottom ash and crushed rock aggregates. High water absorption of the alternative fine aggregates causes a significant decrease in the workability. Increase in the carbonation depth is observed for all alternative fine aggregates used concretes. Higher sorptivity is found for the concretes comprising alternative fine aggregates except for recycled concrete and recycled glass aggregates. The inclusion of recycled ceramic and copper slag aggregates improved abrasion resistance of concrete.