新疆某黄土的土水特征及其分形描述

本研究采用新疆某引水渠道边坡的黄土填料进行土水特征曲线试验,研究压实度和应力水平对土料的土水特征的影响规律。针对试验结果,本研究首先采用经典的van Genuchten模型进行曲线拟合。然后采用分形理论进行土水特征曲线的比较分析。结果表明:(1)随着压实度的增加,土水特征曲线向下移动;随着轴向应力的增加,土水特征曲线也会有所下移;(2)相应于孔隙分布,该土料的土水特征曲线具有明显的分形特性;(3)在相同压实度下,不同应力水平的SWCC分形拟合基本平行。采用本文所述的分形方法,在已知不同应力水平下的孔隙率时,可较为合理的从一个应力水平下的土水特征曲线推求其它应力水平下的土水特征曲线。

The soil-water characteristics and the fractal feature of a typical loess in Xinjiang

In this research, laboratory tests were performed using an infilled loess material from a channel slope in Xinjiang, to investigate the soil-water characteristics of the material which are affected by the de-gree of compaction and the stress level. In this article, the classical van Genuchten''s equation was used firstly on the test results to obtain best-fitted curves. And then the fractal theory was adopted to conduct comparison between the SWCCS. Some conclusions are drawn below:(1) With the increase of the degree of compaction or the increase of the axis stress, the SWCC could move downward to some extent. (2) In contrast to the distributions of pores, the SWCCs of the material shows obvious fractal characteristics. (3) The curves of the SWCC from fractal fitting are parallel at different stress levels but the same degree of compaction. Adopting the fractal method suggested in this article, the SWCC could be predicted from a known curve.