Re-use of concrete/brick debris emerged from big earthquake in recycled concrete with zero residues

Abstract

Nepal’s big earthquake in 2015 caused the accumulation of about 18.85 million tons of debris. Nepal Government was failed to address the management of demolished concrete/brick debris. The samples of concrete/brick debris were collected from the demolished building site and were disintegrated into coarse aggregates, fine aggregates, and powder materials. The recycled coarse aggregate was properly washed to eliminate the contaminants. Recycled bricks were used in both oven-dry (OD) and saturated surface dry (SSD) conditions. The use of 100% recycled coarse aggregate increased the slump from 3 cm to 5 cm and 28-day compressive strength was increased by 4.5%. The slump value of 20% SSD brick aggregate was increased to 5 cm with the decrease of compressive strength by 15% respectively. However, the use of 20% OD aggregate did not affect the slump value. It increased the strength by 10.1%. The use of recycled fine aggregate decreased the slump but the powder increased it. 10% and 20% recycled powder decreased the strength by 24.2% and 27.3% respectively. It was 7.3% and 8.9% respectively for the case of recycled fine aggregates. It is recommended to use the proposed recycling system to manage all remaining concrete/brick debris to make the cities clean and smart.