Experimental Investigation on Mechanical and Durability Properties of Recycled Aggregate Concrete Incorporating Fly ash and Silica fume

Abstract

In the field of civil engineering, resources for making concrete are reduced day by day. So ingredients which are used for making concrete should be reused. Aggregate can be reused and produced recycled aggregate to replace natural aggregate in concrete. Recycled aggregate are comprised of crushed, graded inorganic particles processed from the materials that have been used in the constructions and demolition debris. The difficulty in using natural coarse aggregates for the production of concrete associate with the climate issues of natural aggregates makes the usage of recycled aggregate concrete (RAC) is the prime importance to protect the environment. Recycled aggregates are the aggregates produced from the processing of previously used construction materials such as concrete or masonry. Construction and demolished waste, tested specimens from laboratory, concrete from ready mix concrete plants and precasting units are some sources of recycled aggregate. In this work, recycled aggregate from laboratory waste used to make recycled aggregate concrete. Laboratory waste consists of concrete waste which includes only aggregates. Physical properties such as fineness modulus, density, specific gravity, water absorption of recycled aggregate are investigated. In experimental work recycled aggregate used as 0%, 50%, and 100%. Cement is replaced with flyash and silicafume by 15% and 10% respectively in 50% and 100% recycled aggregate concrete. The results of mechanical properties and durability properties are compared. Results shows that as recycled aggregate content is increased in concrete, mechanical and durability properties are decreased. Cementitious material like silicafume and fly ash somewhat helps to improve the properties of recycled aggregate concrete.