Frost heave is a frost action when the soil temperature is below freezing temperature. Construction in cold regions is difficult and might cause serious damage to structures. Therefore, it is important to estimate frost heave before construction. The purpose of this study is to introduce and modify a model that can predict frost heave behavior through the change in soil porosity. The Porosity Rate Model (PRM) is possibly applicable for engineering purposes in describing the frost heave process, but the previous studies only focus on clayey soils which may not be frost susceptible soils. This paper presents an assessment of PRM on frost susceptible soils prepared by sand-silt mixtures. Comparisons were made by comparing the predictions obtained with the same initial conditions on the PRM using frost heave data for frost-susceptible soils. Results show good agreement between them, PRM was found to be equally applicable to frost-susceptible soils.
Permafrost, as well as seasonally frozen ground, refers to near-surface soil that remains at or below 0 ˚C (32 ˚F) for at least 15 days per year. It is found in high latitudes and high elevations, typically in areas with an annual average temperature of -2˚C (28.4 ˚F) or lower. Permafrost can be composed of any type of soil, including sand, clay, and organic matter. It is estimated that about 24% of the land in the Northern Hemisphere is covered by frozen ground. Within, especially the seasonally frozen soil (annual winter freezing of soil), frost action such as frost heave is observed in frost-susceptible soils. Frost-susceptible soils are distinguished by their vulnerability to freezing, which results in the upward movement of the ground surface induced by frost heave. Frost heave is a phenomenon that occurs when the freezing of soil causes ice lensing, pushing the ground surface upwards. Ice lens formation starts when the temperature of the soil drops below the freezing point of pore water with sufficient water supply. The frozen fringe refers to the partially frozen zone that exists between the growing ice lens and the warmest soil containing pore ice. This zone is characterized by a gradual transition between fully frozen and unfrozen soil (Miller, 1972). According to Rempel (2007), the process of ice lens formation commences with the immediate nucleation of ice behind the frozen fringe. Subsequently, water from both the surrounding voids and the unfrozen region of the soil is drawn toward the site of nucleation and contributes to the subsequent growth of the ice lenses. The volume expansion of soils resulting from frost heave can exert unexpected pressure on foundations and other structural elements, leading to cracks and other types of damage. These issues can necessitate costly repairs and, in extreme cases, even result in structural collapse. Additionally, frost heave can impact the stability and integrity of infrastructure, including roads and underground pipelines, potentially disrupting transportation and the delivery of essential services. While there were notable publications in the late 1920s (Taber, 1929) that contributed to understanding the phenomenon of frost heave in soils, modeling efforts did not begin until later. A reliable numerical simulation model is crucial in predicting the specific amount of frost heave and providing a reference for the design of building structures. It can also help maximize the avoidance of potential dangers caused by frost heave in the design stage. This study aims to generalize a porosity rate model that can predict the frost heave accurately for clayey soil.
