ABSTRACT
The significance of ground freezing is becoming ever more germane, because the design of new urban tunneling systems requires more complex geometries and higher strengths of the improved subsoil, which are limited with conventional construction methods. Therefore, advanced constitutive models for frozen soils must be developed and implemented in commercial Finite Element Analysis (FEA) codes for ground freezing designs under such complex conditions. This study presents a recently proposed elastic-viscoplastic model describing the rate-, stress-, and temperature-dependent mechanical behavior of frozen soils under compressive and tensile loading along with its implementation in a FEA code. After calibrating and validating the model for frozen Fairbanks silt, we simulated the construction of a twin-tunnel excavation supported by frozen soil bodies and compared the numerical results with experimental data from the literature. The good agreement demonstrates the model’s ability to predict the stability and evaluate the deformations of frozen soils in tunneling scenarios.
