The present study takes the ratio of the matric suction to the net vertical stress and the ratio of the matric suction to the net mean stress as new unsaturated stress levels and , respectively. Based on the laboratory tests and theoretical derivation, the modified one-dimensional Mesri creep model and three-dimensional creep model were established, which takes the unsaturated stress level into account. Then, the one-dimensional and three-dimensional creep characteristics of the unsaturated viscous subsoil of an airport under different unsaturated stress levels were analyzed. The following conclusions could be drawn: (1) under different stress levels, the one-dimensional creep deformation of unsaturated soil has a power function relationship with time, and the change rate exponentially decreases with the stress level, which can be well-expressed by the proposed modified one-dimensional Mesri creep model; (2) under different stress levels, the three-dimensional creep strain of the unsaturated soil shows a hyperbolic curve with time and a near-linear relationship at the semilogarithmic coordinate, which can be well-expressed by the proposed modified three-dimensional creep model; (3) under different stress levels, both the one-dimensional creep and three-dimensional creep of the unsaturated soil can be divided into two stages, which are the accelerated creep stage and stable creep stage.

中文翻译：

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基于非饱和应力水平的机场粘性地基蠕变特性研究

本研究中采用的吸力的比净垂直应力和吸力的净平均应力作为新的不饱和的应力水平的比值和，分别。在室内试验和理论推导的基础上，建立了考虑非饱和应力水平的修正一维梅斯里蠕变模型和三维蠕变模型。然后，分析了机场在不同饱和应力水平下的非饱和粘性土的一维和三维蠕变特性。可以得出以下结论：（1）在不同应力水平下，非饱和土的一维蠕变变形与时间呈幂函数关系，其变化率随应力水平呈指数下降，可以很好地表示为提出的改进的一维Mesri蠕变模型；（2）在不同的压力水平下，非饱和土的三维蠕变应变在时间上呈双曲线，并且在半对数坐标处呈近似线性关系，可以通过改进的三维蠕变模型很好地表达。（3）在不同应力水平下，非饱和土的一维蠕变和三维蠕变可分为两个阶段，即加速蠕变阶段和稳定蠕变阶段。