改性黄土渗透性与孔隙结构的依存关系

Responsibility of permeability of modified loess soil on microstructure

摘要: 利用扫描电子显微镜和ImageJ图像处理软件对不同膨润土掺量黄土试样的微结构和孔隙特征进行了统计分析,并与柔性壁渗透仪渗透试验结果进行了对比。电镜观察及孔隙统计结果表明,随着膨润土掺量不断增加,附着在黄土骨架颗粒上的蒙脱石等粘土矿物持续增多,黄土的孔隙数量急剧增多,相反,孔隙平均面积和平均直径呈下降趋势。将膨润土改性黄土的渗透系数与不同大小孔隙的面积比进行统计回归,发现大中孔隙对渗透系数有决定意义。以此为依据,建立渗透系数与有效孔隙隙比之间的关系,提高了传统回归关系的可靠程度。

Abstract: A quantitative statistics of the microstructure of loess soil modified by bentonite in various contents were conducted with scanning electron microscope and ImageJ software to study the responsibility of the permeability on pore structures.The flexible-wall permeameter test illustrated that hydraulic conduvtivity(k) of loess soil was lowered by an increasing addition of bentonite,corresponding to an elevated smaller pores.It was found that a linear relationship existed between lgk and the big an...