中文摘要：

假定冻胀是由冻土内冰透镜体的生长引起的；冰透镜体的生长由热力学 Clapeyron 方程控制，并且依赖于已冻结区与未冻结区之间冻结缘是否存在。未冻水和冰共存于冻结缘的孔隙中；冰水交界面处的吸力使水产生流动，并为冰透镜体的生长补给水分。同时，通过定义1个新的简单的“有效应力”的概念，来判断是否会萌生新的冰透镜体，并提出1个简单的冻胀模型。该模型仅通过几个简单的土的参数，就可以计算土体冻胀量及冻结深度。在此基础上，利用所建立的模型对不同土的冻胀敏感性进行分析。土的冻胀敏感性必须结合环境条件来评估，如上覆压力、温度梯度、降温速率及地下水位埋深等；而某些土在传统的分类中属于弱冻胀土，但在一定环境条件下，仍会产生显著的冻胀量或冻胀压力。

英文摘要：

Frost heave is assumed to be caused by the formation of ice lenses in a freezing soil. The formation of ice lenses is governed by the Clapeyron equation of thermodynamics and relies on the existence of a frozen fringe between frozen and unfrozen zones. Both unfrozen water and ice co-exist in pores of the frozen fringe. The suction at water-ice interface is the driving force for water flow that feeds the growth of ice lens. The initiation of a new ice lens is governed by a simple effective stress concept. Then a simple frost heave model is presented. The frost heave model contains only a few soil parameters and can be used to compute frost heave and frost penetration in stratified soil profiles. The second part of the paper illustrates the application of the frost heave model in assessing the frost susceptibility of different soils. It is shown that the frost susceptibility of a soil must be assessed together with environmental conditions such as overburden pressure,temperature gradient,cooling rate and the depth of groundwater table. A soil that is only mildly susceptible to frost according to classification can still generate a significant amount of heave or heaving pressure under favourable environmental conditions.