ABSTRACT

Aiming to directly and accurately evaluate the fatigue cracking performance of fiber reinforced cement treated aggregate (F-CTA), this paper proposes a model for predicting the fatigue crack length of indirect tensile tests based on the cracking strain energy equilibrium theory. The fatigue crack propagation law from the proposed model was obtained with the fibers of different lengths (10 mm, 15 mm and 20 mm) and contents (0.9 kg/m3, 2.0 kg/m3 and 3.0 kg/m3) and the results were compared with that based on modulus degradation. Results show that the critical damage factor (0.9) and fatigue crack length obtained from the model based on modulus degradation are overestimated, while the critical fatigue damage density is 0.5-0.8 based on the proposed model. The predicted crack length using the proposed model is close to the measured results, indicating that the proposed model is more suitable for predicting the fatigue cracking of the F-CTA. The optimal fiber length and content were determined as 15-20 mm and 0.9 kg/m³ - 2.0 kg/m³, respectively.