Study of the defrosting behavior of concrete by using Taguchi-based grey relational analysis method

The frozen state of concrete in cold region has a significant influence on the determination of its performance. Scientific elimination of the influence of ice based on the comprehensive understanding of its defrosting behavior is significantly important. In this study, the defrosting behavior of the frozen concrete with different sizes, temperatures, and ice contents was researched by establishing a finite element model. The Taguchi–grey relational analysis (GRA) method was used to seek the numerical relationships among various factors. The simulated results show that the temperature field was highly consistent with the tested temperature history of concrete. The defrosting behavior of frozen concrete could be divided into three stages, and the time point at the completion of the Stage II was recommended as the defrosting time of concrete. Furthermore, temperature, size, and ice content affected the defrosting behavior of concrete by influencing the characteristics of different stages. The influence of ice on the determination of concrete performance could be easily eliminated at a higher temperature, a smaller size, and a lower ice content. Size played a more important role in the defrosting behavior of concrete than temperature and ice content. Eventually, a simplified equation for quickly estimating the defrosting time of concrete was proposed.