Test Methods for the Characterization of Polypropylene Fiber Reinforced Concrete: A Comparative Analysis

Abstract

Fiber reinforced concrete (FRC) has been used for many different construction applications and many testing protocols have been developed to determine their mechanical behavior. The present paper focus on the comparisons between four major mechanical tests used for FRC: EN 14651, ASTM 1609, ASTM 1550 and EN 14488. Polypropylene fibers were used as reinforcement in volume ratios of 3 kg/m3, 6 kg/m3 and 10 kg/m3 in a self-consolidating high-strength concrete. The flexural beam tests according to ASTM 1609 and EN 14651 standards were carried on through a closed loop type of control. Comparisons include crack post-peak strength and energy absorption values. The EN 14651 showed to be more precise for low ductile concretes (i.e., low fiber volume fractions). This is due to the notch in the EN standard and different methods used for instrumenting the specimen. The EN 14488 due to its boundary conditions showed much higher results with a deflection-hardening type of behavior. Since the EN 14488’s frame comes into full contact with the specimen, that creates a more rigid material response. This response differs from the other three tests since their support conditions allow rotations and induces cracks to appear in determined locations.