Reliability analysis of fiber concrete freeze–thaw damage based on the Weibull method

摘要

Due to special climatic and environmental factors in the cold regions of north China, the degradation of concrete durability caused by freeze thaw cycles has been a widespread concern among researchers. Freeze thaw damage has seriously affected the safe use and long-term operation of concrete structures. In this study, steel fiber and polypropylene fiber double-blended fiber concrete were selected for an investigation on the law of mass loss and relative dynamic elastic modulus changes from the rapid freeze thaw method. Based on the Weibull probability method, the damage model was established by using mass loss and relative dynamic elastic modulus as the index to carry out freeze thaw reliability analysis. The results show that both the mass loss and the relative dynamic elastic modulus increase gradually under the freeze thaw cycle, but the mass loss increase is more significant. The Weibull probability distribution can effectively describe the degradation law of the frost resistance of concrete specimens. In the reliability index, the mass loss is more sensitive than the dynamic elastic modulus. Through the test data, the reliability function established by this method can directly reflect the relationship between concrete reliability and the freeze thaw cycle, and it can also reflect the remaining life of concrete specimens.