ASSESSMENT OF RECYCLED CONCRETE AGGREGATE (RCA) USAGE IN CONCRETE

Abstract

Recycling concrete is a significant step towards eco-friendly construction practices. The use of recycled concrete aggregates in new structures provides a sustainable development. Initially, recycling of demolition waste was first carried out after the Second World War in Germany and henceforth, there have been reduction in the quantity of construction and demolition waste; and at the same time, it lessened the depletion of natural resources by providing an alternative. There have been recorded cases of application of recycled aggregate(RA) in a large number of construction projects of many European, American, Russian and Asian countries. The test results of ductility and the stiffness of beams with RA are equal or higher than those with natural aggregate. However, concrete made with recycled concrete aggregates exhibits different engineering properties. This difference is mainly due to the attached mortar paste on recycled concrete particles. Recycled aggregates have been found to have high water absorption capacity, which affects various properties mainly mechanical performance of the resulting concrete mix. Based on previous research, this paper presents a comprehensive overview of the recycled concrete material characteristics and the effect of using recycled concrete material on the mechanical properties, the durability properties and structural performance of concrete so as to help relevant units and staffs in the practical work.