Abstract: The expansion of water-filled fractures under freeze-thaw cycles inevitably leads to the damage and fracture of rock bridges as well as the deterioration of their physical and mechanical properties. To investigate the effects of freeze-thaw cycles on the expansion of water-filled fractures and damage to rock bridges, as well as their impact on the deterioration of the rock’s physical and mechanical properties, this study conducts freeze-thaw cycle experiments and eccentric loading tests on rocks with prefabricated fractures. It analyzes changes in red ink migration and acoustic emission activity during the freeze-thaw process and further established a mechanical model for the evolution of rock bridge damage. The results show that: ①with an increase in the number of freeze-thaw cycles, the distribution range of red ink and acoustic emission events within the rock bridges continuously increases, indicating a gradual increase in the fracture range of the rock bridges. ②Acoustic emission events inside the water-filled fractures are mainly induced by the damage and fracture of ice, while those outside the fractures are primarily caused by the damage and fracture of the rock itself. ③The process of frost heave expansion in water-filled fractures induces highly uneven acoustic emission activities （event density and energy density） in different areas. ④Under eccentric loading conditions, as the number of freeze-thaw cycles increases, the plastic characteristics such as yield deformation and stress drop before the peak stress of the rock bridges gradually disappear, leading to a gradual decrease in peak stress and an increase in the rate of strength loss. ⑤Both the freeze-thaw cycle action and the loading effect can cause damage to the rock specimens, with freeze-thaw damage increasing as the number of cycles increases. In summary, this study not only thoroughly analyzes the mechanisms of damage to rock bridges caused by freeze-thaw cycles but also provides an important reference for understanding the mechanical behavior of rocks under freeze-thaw conditions.