Abrasion resistance, compressive strength and elasticity modulus of recycled aggregate concrete (RAC) included lower quality recycled aggregate with and without silica fume

Abstract

The usage of recycled aggregate (RA) for concrete works is spreading for gaining wide acceptance around the world, and total amount of RA utilized in concrete industry increases day-by-day. RA is used in many concrete products, such as concrete interlocking blocks, pavements, etc. One of the physical causes of concrete deterioration is surface wear or loss of mass for concrete products which are especially exposed to vehicular traffic (i.e., industrial floors and pavements). Besides, the loss of mass by concrete surface wear becomes the primary factor of one or more processes of chemical deterioration as a result of an increase in permeability due to mass loss of the concrete surface wear. The main goal of this research is to investigate the abrasion behavior of recycled aggregate concrete (RAC) with/without silica fume (SF) related with the mechanical and the physical properties of RAC. In this research, lower quality RA (<15 MPa) is utilized as recycled coarse aggregate (RCA1 and RCA2) and recycled fine aggregate (RFA) with 25, 25, and 50% replacement ratios, respectively, in concrete mixes. As a result, RCA2 with/without SF gives better performance than RCA1 and RFA if abrasion resistance is considered only. Besides, RFA utilization in concrete decreases the abrasion performance of RAC. Also the relations of compressive strength-abrasion loss and elasticity modulus-abrasion loss are examined, and high regression coefficient (R) for the relations is found. Keywords: abrasion resistance, mechanical properties, physical properties, recycled aggregate, silica fume