Modeling unconfined compression behavior of frozen Fairbanks silt considering effects of temperature, strain rate and dry density

Abstract

Many studies have been conducted to understand the mechanical characteristics and modeling the stress-strain behavior of frozen soils. Yet there is still a need for simple models that are capable of capturing the effects of important parameters such as temperature, strain rate, and dry density on the behavior of frozen soils. This paper re-analyzed the unconfined compression test results of ice-poor frozen Fairbanks silt, used a simple model to simulate the stress-strain behavior, and verified the effectiveness of such model in accounting for the effects of temperature, strain rate, and dry density. Key mechanical properties such as peak compressive strength, initial yield strain, and Young's modulus were analyzed, and new empirical equations were proposed to correlate these key mechanical properties with temperature, strain rate, and/or dry density. A simple model was calibrated for ice-poor frozen Fairbanks silt. Comparison between the model-simulated stress-strain curves and test data shows it is very effective in accounting for the effects of these parameters on the stress-strain behavior within a large range of temperature, strain rate and dry density. Furthermore, comparison of the model-simulated stress-strain curves with independent test data shows that this model is also effective in predicting the stress-strain behavior of Dalian frozen silt. These empirical equations and the model can be used for simulating the mechanical behavior of ice-poor frozen Fairbanks silt or other similar frozen silts under unconfined or low-confining pressure conditions.