Use of recycled concrete aggregate and granulated blast furnace slag in self-compacting concrete

Abstract

Abstract In civil engineering industries, mass utilization of concrete has prompted to use recycled aggregates and slag as one of the strategies and an option for whole range of possibilities in the use and reuse of construction materials in civil industry. In this paper, an investigation is carried out to study the fresh and harden properties of granulated blast furnace slag (GBS) based normal vibrated concrete (NVC) and self-compacting concrete (SCC) with partial replacement of natural coarse aggregate (NCA) with recycled concrete aggregate (RCA). The testing on constituent materials is conducted as per Indian code of practice. The tests on fresh NVC and SCC were conducted as per the Indian standards and EFNARC guidelines respectively. The tests on harden state of concrete include the compression test on cube specimens as per the Indian standards. The present study is limited to investigate the fresh and harden properties of GBS based NVC and SCC with partial replacement (0%, 20%, 25%, 30%, and 35%) of NCA with RCA with a mean target compressive strength of 30 N/mm2. The topographic and compositional analysis on samples of both NVC and SCC group specimens is determined using the Scanning electron micrograph (SEM). From the present study it is concluded that the compressive strength of the GBS based SCC group specimens with NCA replaced by RCA of more than 20% s showed reduction in compressive strength both for 7-day and 28-day results in comparison to respective NVC group specimens.