Evaluation of the mechanical performance of M25 grade recycled aggregate concrete

Abstract

Recycling, sustainability and environmental stewardship are some of the concepts that are in the front line now-a-days. Some strategies that can be adopted in order to bring these concepts in to the construction processes are the efficient use of materials, use of recycled materials, reduction in the waste materials produced etc. Use of recycled concrete aggregates as a substitute for natural (virgin) aggregates is a way to bring in these concepts into the manufacture of concrete. An experimental investigation was conducted to assess the effect of replacement of normal coarse aggregate with recycled coarse aggregate (prepared from old concrete specimens) on M25 grade concrete. Different levels of replacements studied include 0%, 20%, 50%, 80% and 100% were considered. The properties studied are fresh properties as well as mechanical properties which include compressive strength, split tensile strength and flexural strength. It is concluded from the study that as the RCA content increases, it is necessary to increase the cement content and or to decrease the water cement ratio in order to attain target compressive strength.