Temperature and Freeze-Thaw Effects on Dynamic Properties of Fine-Grained Soils

摘要

Consider that the Mable Creek silt in central Alaska liquefied during the November 2002 earthquake. Subsequently, frozen samples of these fine-grained soils were retrieved for laboratory study. This paper presents the influence on dynamic properties by temperature changes from below freezing to near freezing, and by freeze-thaw cycles. Sample temperature change was simulated by gradually applying the increasing temperatures of -0.2, 0.5, 1, 5, and 24 degrees C. Sample seasonal climate change was simulated by applying 1, 2, and 4 freeze-thaw cycles. Tests on specimens conditioned at 0.5 and -0.2 degrees C through different thermal conditioning paths were also performed. Determination of the soil's dynamic properties was investigated using triaxial strain-controlled cyclic tests. The shear modulus was found to decrease when the temperature increased from near freezing to above freezing; however, the damping ratio reached a maximum value when temperature was at or near freezing. Applying 1, 2, and 4 freeze-thaw cycles resulted in an increase in both the dynamic shear modulus and the damping ratio. Thermal conditioning paths with the same target near-freezing temperature were found to impact dynamic properties.