Fatigue performance of ultra-high-performance concrete (UHPC): A critical review

Concrete fatigue is a significant concern under repetitive loadings. Particularly, the fatigue life typically improves for Ultra-High-Performance Concrete (UHPC). This study aims to thoroughly evaluate the fatigue performance of UHPC by reviewing existing literature and considering various factors such as stress levels, temperature, material characteristics, loading frequency, and the role of coarse aggregate. It also presents multiple fatigue models and S-N curves. The results indicate that the available studies do not comprehensively cover the fatigue performance of UHPC. Certain elements, like incorporating carbon materials in UHPC, positively influence fatigue performance, whereas high-stress levels reduce fatigue life. Additionally, fatigue life is adversely affected in low temperatures. While it is challenging to isolate the effects of individual factors on fatigue life and performance, the combined influences of stress intensity and loading frequency are notably significant. The paper also identifies several potential areas for further research on UHPC fatigue.