ABRASION RESISTANCE OF CONCRETE AS INFLUENCED BY INCLUSION OF FLY-ASH

This research was conducted to evaluate abrasion resistance of high-vo lume fly ash concrete. A reference plain portland cement concrete was proportioned to obtain 28-day strength of 41 MPa. Concrete mixtures we re also proportioned to have two levels of cement replacements (50 and 70%) with an ASTM Class C fly ash. Abrasion tests were carried out us ing the rotating cutter method as per ASTM C-944. In this work all the concrete specimens made either with or without fly ash passed the abr asion resistance requirements per ASTM C-779, Procedure B. An accelera ted test method was also developed to evaluate abrasion resistance of concrete. This method used the rotary cutter device having dressing wh eels equipped with smaller size washers. A measured amount of standard Ottawa sand was added to the surface being abraded at one minute inte rvals. The accelerated test results exhibited lower abrasion resistanc e for high-volume fly ash concrete systems relative to no-fly ash conc rete.