Flexural Fatigue Strength and Design by the P-S-N Curve for HVFA Pavement Concrete
Yasuhiro KATOH, Sumio HAMADA, Takao ICHIOKA and Ryota KOBAYASHI
Abstract:This paper describes flexural fatigue strength of concrete with high volume fly ash (HVFA concrete). The number of coal-fired power plants has been increasing, and amount of coal ash will increase gradually in Japan. Proper use of coal ash is urgently needed. Long term increase of flexural strength of HVFA concrete is expected. From the life cycle cost performance, HVFA concrete suits for pavement concrete. Since Japanese normal pavement concrete design method requires the flexural fatigue strength, this study aims to investigate the flexural fatigue strength of HVFA pavement concrete. Fatigue test results have large scatter, and this scatter includes a scatter of concrete materials strength mixed in several batches. All test specimens were made from only 2 batches in order to exclude scatter of materials strength. From the flexural fatigue tests, the relation (P-S-N curve) between S-N curve and the life probability are obtained based on the normal and 3 parameter Weibull distributions. Based on the fatigue test results, the strength at 2 million repetitions are determined from these distributions. Resultantly, the S-N curve of HVFA pavement concrete is almost same as the normal pavement concrete. The P-S-N curve of HVFA concrete obtained from the normal distribution does not have a large difference to that obtained from 3 parameter Weibull distribution. Key Words:Concrete pavement, High volume fly ash(HVFA), Flexural fatigue strength, S-N curve, Life probability, P-S-N curve