重塑黄土崩解特性试验研究

Experimental Study on Disintegration Characteristics of Remolded Loess

为研究重塑黄土的崩解特性及其与影响因素之间的关系,利用自制崩解试验仪对32种不同干密度、不同初始含水率的黄土试样进行崩解试验,分别得出了试样崩解速率与干密度、初始含水率、有效空隙率的关系曲线,并以土-水特征曲线为基础,分析了试样孔隙结构对其崩解性能的影响。试验结果表明,同一初始含水率下,随着干密度的增加,试样崩解速率呈指数函数形式衰减且衰减速率随初始含水率的增加而近线性增加;同一干密度下,随着初始含水率的增加,试样的崩解速率有降低趋势,但下降趋势并不显著。通过分析干密度、初始含水率与崩解速率的关系,结合试样土水特征曲线,讨论了孔隙结构对崩解速率的影响,并研究了试样崩解速率与有效空隙率的关系,试样崩解速率的分布以有效空隙率等于8%,22%为分界线明显分区,研究认为由于试样制备压实过程中,形成了不同的孔隙结构。

To obtain the disintegration features of remolded loess and their relation with different factors,we conducted tests on 32 loess samples of different initial water contents and dry densities by self-developed disintegration tester.The relationship curves of disintegration rate respectively vs.dry density,initial water content and effective void ratio are obtained.On the basis of soil-water characteristic curve（SWCC）,the effect of pore structure on disintegration property is analyzed.Results show that under the same initial water content,the disintegration rate attenuates exponentially with the increase of dry density,and the attenuation rate linearly increases with the increase of initial water content; while under the same dry density,the disintegration rate shows a tendency of decreasing with the increase of initial water content,but it is not significant.Furthermore,the relationship between disintegration rate and effective void ratio is researched on the basis of the SWCC and the above obtained relationships.Different pore structures are formed in the process of sample preparation,and the distribution of disintegration rate is apparently divided into zones with the effective void ratio of 8％ and 22％ as dividing lines.