Studies on the Mechanical Properties of Recycled Aggregate Concrete using Treated Recycled Coarse Aggregates

Abstract

Abstract The Recycled Aggregate (RA) obtained from C & D (Construction and Demolition) debris, especially from concrete waste is an excellent way to produce concrete sustainably and with an eco-friendly approach. The usage of RA in concrete results in savings of conventional natural materials like river sand as fine aggregate (FA) and crushed granite as coarse aggregate (CA). However, the use of recycled aggregates in concrete has shown a significant diminishment in the concrete hardened properties. Hence, this study aims to develop RA concrete that matches the properties of natural aggregates by adopting aggregate treatment techniques. In this study, two aggregate treatment techniques are adopted i.e., acid treatment using Hydrochloric acid and base treatment using Sodium Hydroxide. Two different grades of concrete were chosen and the NA (natural aggregates) were replaced 100% by untreated RA as well as treated recycled aggregates (treated using acid and base). A detailed comparison has been made between the hardened characteristics of concrete produced with natural, untreated as well as treated (acid and base) recycled aggregates. From the obtained experimental test results it was concluded that both the acid & base treatment methods had yielded better results and the hardened properties were found to be similar to that of the NA concrete.