Effect of Freezing-Thawing on Preconsolidation Pressure

This study aims to assess the impact of freezing-thawing cycles on the preconsolidation pressure of saturated clays. The effect of elevated temperatures and the impact of freezing on the preconsolidation pressure of clays have been investigated. However, there still exists a lack of understanding about how one extreme temperature, such as freezing, impacts the preconsolidation pressure on the other extreme, such as an elevated temperature. In this paper, a modified temperature-controlled odometer is utilized to determine temperature effects on the preconsolidation pressure. One-dimensional consolidation is first performed on two kaolinite clay specimens, one at room temperature (20°C) and the other at an elevated temperature of 40°C. Moreover, another specimen is exposed to a temperature cycle of 20°C to –15° and to 40°C. Then, the specimen is again incrementally consolidated at 40°C. The preconsolidation pressure for each specimen is estimated using the strain energy. We then assess the impact of the freezing temperature applied to the last specimen on the preconsolidation pressure by comparing the pressure between the three considered specimens. The results suggest that the sample experiencing a freezing temperature prior to a heating stage shows a higher preconsolidation pressure.