An Investigation of the use of Recycled concrete as aggregate in fresh concrete production

ABSTRACT 

In recent years there has been an increase in the number of construction works and 

concrete is the main construction material for most of the structures that are being 

built. Nigeria is a developing Country with a large population and land area therefore 

a consumer of concrete. This paper considers the option of recycling concrete in 

order to meet the high concrete demand and effective management of construction 

and demolition waste. The test focused on the use of recycled concrete as coarse 

aggregate for concrete production. The coarse aggregate component of normal 

concrete was replaced with 100% Recycled Coarse Aggregate (RCA) in a 1:2:4 

cement, sand and aggregate mix proportion and 0.6 water/cement ratio and this 

resulted to 17.13N/mm2 28 days cube strength as against the normal 24N/mm2 for 

normal concrete. The experiment recommends that recycled coarse aggregate can 

serve as a viable resource for manufacturing concrete, especially low strength 

concrete. The economic benefit of RCA concrete includes efficient reuse of 

recovered coarse aggregate from demolished and collapsed buildings and Recycling 

of concrete debris can make a contribution to reduce the total environmental impact 

of the building sector.