Fatigue prediction model of ultra-high-performance concrete beams prestressed with CFRP tendons

In the present paper, a comprehensive study on the flexural fatigue behavior of ultra-high-performance concrete (UHPC) beams prestressed with carbon-fiber-reinforced polymer (CFRP) tendons is reported. A total of two UHPC beams prestressed with CFRP tendons were experimentally investigated. On the basis of the fatigue constitutive model of the materials, a fatigue prediction model (FPM) was developed to simulate the flexural fatigue evolvement of the beams. The strain and stress in UHPC and CFRP tendons were calculated by the sectional stress analysis. The influence of steel fiber was considered in the formulae for the crack resistance and crack width, and the midspan deflection was calculated using the sum of deflection before cracking and increment after cracking. The obtained test results were used to verify the FPM. A parametric study was then conducted to analyze the fatigue development of such component, and a formula to predict the flexural fatigue life of UHPC beams under different fatigue loads was proposed.

Automated summary

This paper comprehensively studied the flexural fatigue behavior of UHPC beams prestressed with CFRP tendons and developed a fatigue prediction model to simulate the fatigue evolution. The research considered the fatigue constitutive model of materials and analyzed the performance of UHPC and CFRP tendons by calculating strain and stress, while also taking into account the influence of steel fibers on crack resistance and deflection.