中文摘要：

饱和土与非饱和土之间及非饱和土之间在力学性质上的差别主要是由于它们饱和度的不同而造成的．以饱和度作为参变量，以现有的比较成熟的土的本构理论作为基础，充分考虑饱和度的变化对土的工程性质的影响，根据塑性硬化理论和临界状态以及屈服面的概念，研究了非饱和土的流动法则和硬化规律，导出了非饱和土的应力应变增量公式，建立了一种较为简单的描述非饱和土应力应变特性的本构模型，为丰富和进一步完善非饱和土的本构理论作了有希的探讨．该模型具有广阔的工稃府用前景．

英文摘要：

The reasons why there are the differences in mechanical characters between satured and unsatured soil are made the different degree of their saturation. On the basis of matured character theories, take the saturated degree as a variable parameter, the flow law and harden one of unsatured soil was studied, the stress-strain increment formula for unsature soil was given and a simple character model was constructed to describe the stress-strain characters unsatured soil. The model is helpful to enrich and perfect character theory of unsatured soil and has a wide prospect in engineering.