Strength Characteristics of Frozen Fox Gravel

In contrast to data available on strength and deformation characteristics of frozen soils, frozen gravels have received relatively little attention. This seems to be related to fewer geotechnical projects conducted in frozen gravels, the relatively higher stability of frozen gravels, and possibly greater difficulty in conducting mechanical measurements in or on frozen gravels. Findings presented in this paper came from a testing program conducted on artificial samples using gravels from Fox, Alaska. Main variables controlled during testing were strain (straining) rate, temperature, and size and shape of the tested samples. All tests were run in uniaxial compression. After preliminary testing of straining rate influence, all remaining tests were run at a constant strain rate of $10\mu \epsilon /s\text{.}$ Temperature at which tests were conducted and volume of samples were found to be the controlling variables. Their effect correlates well to exponential models, which describe gradual decrease of strength with temperatures approaching the thaw level and with decrease in sample volume. The data may find applications in analysis of stability of openings and foundations constructed in frozen gravels.