Experimental and numerical investigations on frost damage mechanism of a canal in cold regions

• A numerical water-heat-mechanics model is set up and corresponding computer program is developed.
• A model test on a canal is carried out in one freezing–thawing cycle to analyze the frost heave mechanism.
• The canal model is simulated to analyze its temperature, water and mechanical states during the freezing–thawing process.

Frost action is a prevailing and heavy damage to canals in cold regions, and it involves complicated heat and mass transfer as well as frost deformation in the seasonal freeze–thaw ground. To explore the frost damage mechanisms of canals in cold regions, firstly, a numerical water-heat-mechanics model is set up and corresponding computer program is developed. Secondly, a model test on a canal is carried out in one freezing–thawing cycle. Then, the canal model is simulated to analyze its temperature, water and mechanical states during the freezing–thawing process. The results show that under the drive of temperature, the total water contents in freezing–thawing fronts are very high and even a part of the freezing front is filled with ice and unfrozen water, which causes high tensile stress and heavy frost heave. In particular, the deformations at the toe of the canal slope are much larger than those in other zones. Therefore, this zone should be monitored closely to ensure safe operation. As a preliminary study, the experimental and numerical model and results in this study may be a reference for design, maintenance and research on other canals in cold regions.