Influence of natural coarse aggregate type on the transport properties of recycled concrete

ZEGA, C.; DI MAIO, A.; ZERBINO, R.

JOURNAL OF MATERIALS IN CIVIL ENGINEERING

ASCE-AMER SOC CIVIL ENGINEERS

Lugar: Reston, Virginia; Año: 2014 vol. 26 p. 40140061 - 40140069

0899-1561

The use of recycled concrete represents a friendly environmental solution for minimizing the impact of the construction and demolition wastes. In many countries, the incorporation of recycled coarse aggregates (RCA) is a common practice, being the maximum contents of RCA usually limited to around 25% of the total content of coarse aggregate. The incorporation of higher volumes of RCA represents a field of discussion mainly regarding to the concrete durable behaviour. This paper analyzes different transport properties of 20 to 50 MPa compressive strength concretes prepared with variable contents of RCA (0, 25, and 75%). Eight types of RCA were obtained from concretes incorporating four different natural coarse aggregates: granitic, basaltic, and quartzitic crushed stones and siliceous river gravel. Capillary absorption, water penetration and chloride diffusion tests were performed. The variation of transport properties with concrete compressive strength and the effect of RCA content on the transport properties variability were analyzed. According to the results obtained, the durable behaviour of recycled concretes will be different according to the transport mechanisms at which are exposed and it can be as good as that of concretes made with natural coarse aggregates.