考虑孔隙比和水力路径影响的非饱和土土水特性研究

以非膨胀性黏土为试验研究的对象,利用压力板法研究了初始孔隙比对不同水力路径下非饱和压实土土水特性的影响。试验结果表明,不同初始孔隙比土水特征曲线均存在明显的滞洄现象;当吸力大于某一值时,以含水率与吸力关系表示的话,不同初始孔隙比主脱湿土水曲线几乎重叠;以饱和度与吸力关系表示,初始孔隙比对土水特征曲线存在较大的影响。还提出归一化处理全吸力范围内不同初始孔隙比土水特征曲线的方法。最后,在归一化的处理方法基础上,提出了考虑初始孔隙比影响的非饱和土滞洄特性的模拟方法,并利用相关实测数据加以验证。

Soil-water characteristics of unsaturated soils considering initial void ratio and hydraulic path

To investigate the effects of the initial void ratio on the soil-water characteristic curves of non-expansive clay under different hydraulic paths, the suction is imposed or measured using the pressure plate method. The experimental results show that the obvious hysteresis phenomenon can be observed in the soil water characteristic curve (SWCC) with different initial void ratios. The main drying SWCCs of compacted specimens with different void ratios coincide with each other at the suction higher than a specific suction value when they are expressed by the relation between suction and water content. When the SWCC is expressed by the relation between suction and degree of saturation, the influence of the initial void ratio is highlighted. Moreover, a method to normalize the main drying and wetting SWCC in full suction range is proposed. Finally, a method to describe the hydraulic hysteresis behavior of specimens with different initial void ratios is proposed, and the predicted results are compared well with measured values.