Improved flexural fatigue resistance of PVA fiber-reinforced concrete subjected to freezing and thawing cycles

Abstract

This paper investigates the effect of PVA fiber-reinforcement on the flexural fatigue behavior of concrete subjected to freezing and thawing cycles. Plain and PVA fiber-reinforced concrete specimens were exposed to freezing and thawing cycles, then a flexural fatigue test using a wheel load was performed with a stress level in the range of 0.5-0.9. The effect of PVA fiber reinforcement on the flexural fatigue resistance was evaluated by the stress ratio-fatigue life (S-N) relationship. The flexural fatigue test results showed that repeated freezing and thawing actions not only reduced the static strength but also dramatically diminished the resistance to fatigue failure. In addition, a low interrelationship of the S-N relationship of concrete subjected to freezing and thawing cycles was observed. PVA fiber reinforcement enhanced the flexural fatigue strength of concrete subjected to freezing and thawing cycles due to increase in (1) the resistance for freezing and thawing action and (2) the resistance for flexural fatigue failure. Finally, empirical formulas for the S-N relationship of plain and PVA fiber-reinforced concretes subjected to freezing and thawing cycles are proposed based on the experimental investigation.