Microstructural investigations of fiber-reinforced into the abrasion resistance concrete floors

The influence of fiber inclusion on the abrasion resistance of concrete specimens of various mix compositions was measured by means of a rolling-wheel apparatus. Microhardness, mercury intrusion porosimetry, and petrographic examinations were used to investigate the microstructural features of the cement matrix of the exposed surfaces. The results indicate that variations in the watercement ratio for both plain and fiber-reinforced concrete mixes influence the microhardness and the pore structure of the surface matrix. The petrographic examination revealed that variations in the water-cement ratio for both plain and fiber-reinforced concrete influenced the formation and dimensions of the locally abundant microcracks observed below the parts of the surfaces subjected to abrasion testing. For the systems investigated, this was attributed to the phenomenon of rolling contact fatigue.