Liquefaction is a phenomenon in which the strength and stiffness of soil is reduced by earthquake shaking or other rapid loading, causing the soil to behave like a liquid. This can result in ground failures such as settlement, lateral spreading, and loss of bearing capacity, leading to damage to structures and infrastructure. Research in liquefaction focuses on understanding the mechanisms and triggers of liquefaction, developing methods to assess and predict liquefaction susceptibility, and identifying techniques to mitigate its effects. This area of research is important for ensuring the safety and resilience of infrastructure in earthquake-prone regions.