考虑应力作用影响的黄泛区粉土土水特征曲线分析与预测

为了研究应力作用对土水特征曲线的影响，采用应力关联土水特征仪测定不同应力下粉土的脱湿-吸湿曲线，讨论应力变化对粉土土水特征的影响规律，并利用应力与孔隙比的关系提出考虑应力作用的粉土土水特征曲线预测方法。研究发现：试样在应力逐渐增加时不易脱水，但更易吸水，非饱和粉土的持水能力随着正应力的增大而增强；脱湿曲线与吸湿曲线并不重合，有明显的回滞现象，并且吸湿曲线饱和度的变化比脱湿曲线更加剧烈；随着正应力的增大，滞回圈面积减小，滞回特性减弱。此外，将预测曲线与测得的试验曲线对比，可知提出的考虑应力的土水特征曲线预测方法具有较好的预测精度。

Analysis and Prediction of Soil-water Characteristic Curve of Silt in Yellow River Flood Field Considering the Effect of Stress

To study the influence of stress on the soil-water characteristic curve, the wetting-drying curves of silt under different stresses are measured by stress-dependent soil-water characteristic apparatus, and the influence of stress change on the soil-water characteristics of silt is discussed. The prediction method of silt soil water characteristic curve considering stress is proposed, which is based on the relationship between stress and void ratio. It is found that the sample is more difficult to dehydrate when the stress increases gradually, but it is easier to absorb water. The water-holding capacity of unsaturated silt increases with the improvement of normal stress. The wetting curve does not coincide with the drying curve, and there is a clear hysteresis phenomenon. Besides, the saturation change of the wetting curve is more intense than the drying curve. With the increase of normal stress, the area of the hysteresis loop decreases and the hysteresis characteristics weaken. In addition, by comparing the predicted curve with the measured test curve, it can be seen that the proposed prediction method of soil water characteristic curve considering stress has better prediction accuracy.