Reliability analysis of fatigue life of self-compacting concrete subjected to freeze-thaw damage

Abstract:

In order to study the influence of freeze-thaw (FT) damage on the flexural fatigue life of self-compacting concrete, the four-point flexural fatigue tests at different stress levels were carried out on concrete beams subjected to different FT cycles, and the Weibull distribution parameters of flexural fatigue life of concrete beams were obtained by the method of moments. The prediction models for the fatigue life of concrete beams subjected to different FT cycles under different reliability probabilities were established. Results showed that the probability distribution of fatigue life for self-compacting concrete subjected to different FT cycles could be characterized by two-parameter Weibull distribution. The dispersion of fatigue life of self-compacting concrete increased with the increase in FT cycles and decreased with the increase in stress levels. On the basis of the test data, the P_f-S-N curves of self-compacting concrete were generated, which can accurately predict the flexural fatigue life of self-compacting concrete subjected to different FT cycles. The safety factor required for the fatigue life of self-compacting concrete increased with the increase in FT cycles, which indicates that for the self-compacting concrete suffering from more serious FT damage, a larger safety factor should be adopted to ensure the safe operation of the structure.