Apparent fracture toughness of compacted snow using cantilever beam tests

The fracture toughness of compacted snow is a key parameter for understanding its resistance to fracture and evaluating the structural integrity of snow structures. However, data and in situ testing methods for fracture toughness of compacted snow oriented toward cold-region construction remain rarely reported. In this study, an adapted cantilever beam test together with linear elastic fracture mechanics (LEFM) was employed to determine the apparent fracture toughness of compacted snow at temperatures between − 16 °C and − 10 °C. The apparent mode I fracture toughness was obtained from experimental records using analytical formulations verified by finite element analysis (FEA). A total of 25 sets of compacted snow specimens were prepared and tested to examine the effects of span-to-depth ratio ( L / h = 1, 2, 3, and 4) and storage duration (1, 5, 10, 15, 25, and 180 days) on the apparent fracture toughness. The influence of snow density was also analyzed, and a power-law relationship was established. Results indicate that the apparent mode I fracture toughness is relatively insensitive to L / h within the range of 1–4, while it increases gradually with longer storage duration. Compared with previous studies, the apparent fracture toughness is 11 to 63 times that of low-density natural snow, and approximately one-quarter to one-third that of ice. These findings help address the lack of fracture toughness data for high-density snow in the range of 520–630 kg/m 3 . In addition, the proposed testing method shows promise for field application to layered compacted snow structures.