Study on experimental determination of the dynamic elastic mechanical parameters of frozen soil by ultrasonic technique

Velocities of the ultrasonic (dilatational and shear) waves in frozen fine sand, silt (loess) and clay with different water contents were measured at different temperatures by UVM-2 Ultrasonic Measuring System. Then, the dynamic elastic mechanical parameters (dynamic elastic modulus E, dynamic shear modulus G and Poisson’s ratio μ) of the frozen soils tested were calculated in terms of elastic theory based on the measured ultrasonic wave velocities.The calculated results show that both of dynamic elastic modulus and shear modulus of the three types of frozen soils increase with decreasing temperature,and their relations can be described by same formula. The Poisson’s ratios of the frozen soils tested increase with increasing temperature. Both of the dynamic elastic modulus and shear modulus of frozen silt and clay with low water content increase with increase of water content;whereas the moduli of those with high water contents decrease with increasing water content. The Poisson’s ratios of the frozen silt and clay increase with increasing water content in the wide range of water contents tested.