Jäätymissulamisjakso

A jäätymissulamisjakso, or freeze-thaw cycle, refers to a process where a substance repeatedly undergoes transitions between its solid (frozen) and liquid states. This phenomenon is most commonly observed with water in the natural environment, particularly in regions with fluctuating temperatures around the freezing point of water. During a freeze-thaw cycle, water within porous materials like soil or rock expands when it freezes, exerting pressure. As the temperature rises and the ice melts, the pressure is released, and the water can then penetrate deeper into the material. This repeated expansion and contraction can lead to significant physical changes in the material over time.

In geology, freeze-thaw cycles are a primary driver of physical weathering. The expansion of freezing water can break apart rocks, a process known as frost wedging. This contributes to the formation of talus slopes and alters landscapes. In civil engineering, freeze-thaw cycles can damage roads, bridges, and buildings, especially those made of concrete or asphalt. The repeated expansion and contraction can create cracks and weaken structures. Understanding the frequency and intensity of freeze-thaw cycles is crucial for predicting material degradation and designing durable infrastructure in cold climates. The term is also applicable in other scientific contexts, such as in biology for cell preservation or in materials science for studying the behavior of polymers.