Reusing Demolished Concrete Waste for the Production of Eco-friendly Concrete Blocks

Abstract

The rapid expansion of construction and demolition activities has resulted in a substantial accumulation of concrete waste, posing both environmental and resource-management challenges. This study investigates the potential of using crushed demolished concrete waste as an alternative to natural coarse aggregates in the manufacture of eco-friendly concrete blocks. Recycled aggregates were processed from locally sourced demolition debris and incorporated into block mixes at replacement levels ranging from 0 to 100%. Concrete blocks were manufactured under controlled conditions and assessed through compressive strength and density testing at curing ages of 7, 14, and 28 days. Compressive strength was observed to decline systematically with increasing demolished aggregates. However, blocks containing up to 50% recycled aggregates exhibited performance levels suitable for non-load-bearing masonry applications. Higher replacement ratios, while showing reduced strength, remained structurally stable for partition walls and secondary construction uses. The findings confirm that demolished concrete waste can be effectively repurposed into functional masonry units, offering measurable material cost savings and contributing to sustainable construction practices by reducing landfill disposal and natural aggregate consumption.