Growth mechanism of segregated ice and its influence on frost heave characteristics during horizontal freezing

Theories of ice segregation and frost heave developed for vertical freezing cannot be directly extended to horizontal freezing due to significant differences in water migration, segregated ice, and cryostructure between the two processes, resulting in a lack of basis for predicting and preventing frost damage in horizontal freezing. Based on the frozen fringe theory, the growth mechanism of segregated ice and its influence on frost heave during horizontal freezing are further explored. Firstly, experiments are carried out to investigate the particularity of horizontal freezing, the characteristics of frost heave are analyzed, the growth of segregated ice and morphology of cryostructure are characterized, the influence of different factors on segregated ice growth is studied, and the difference of cryostructure between horizontal and vertical freezing is clarified. Then, the mechanical state of ice lenses during segregation in horizontal freezing is analyzed, and the initiation criterion of segregated ice during horizontal freezing is modified, which takes pore pressure as the discriminant factor. On this basis, the controlling equation of ice segregation is derived. Finally, the intrinsic connection between segregated ice growth and frost heave is analyzed, and the influence of segregated ice growth on frost heave characteristics during horizontal freezing is revealed. The results can provide theoretical basis for understanding horizontal freezing and optimizing prevention for horizontal freezing damage.