尾矿砂二维非饱和渗流的实验研究

Experimental study on two-dimensional unsaturated seepage of tailing sand

为研究尾矿砂非饱和渗流,通过自行设计的仪器进行了二维非饱和渗流实验,得到了实验中的基本现象和渗流稳定后含水率沿水平和竖直方向的分布。利用直剪实验测试了非饱和尾矿砂抗剪强度参数与含水率关系。通过分析综合获取了非饱和尾矿砂抗剪强度参数的空间分布,并利用分析结果解释了非饱和渗流中的基本现象。研究结果表明：尾矿砂非饱和渗流中出现了明显的裂缝和错层;非饱和尾矿砂内沿水平和竖直方向含水率分布均近似服从指数规律;粘聚力随含水率的增加先增后减;内摩擦角随含水率的增加单调递减;抗剪强度参数具有空间分布特点;裂缝和错层源于抗剪强度参数的分布与变化。

In order to study unsaturated seepage of tailings,two-dimensional unsaturated seepage experiment was carried out by using self-designed apparatus.Basic phenomenon in the experiment and rate of water content distribution along both horizontal and vertical directions in seepage steady state were obtained.The relation between shear strength parameter of unsaturated tailings and rate of water content was measured by direct shear test.The spatial distribution of unsaturated tailing sand shear strength parameter was obtained through analysis and synthesis,which was used to explain fundamental phenomenon in seepage experiment. Experimental results show that in tailings unsaturated seepage,obvious cracks and staggered floor appear. The rate of water content distribution along horizontal and vertical direction in unsaturated tailings is approximately exponential.With the increase of rate of water content,cohesion first increases and then decrease.Internal friction angle decreases monotonically with the increase of rate of water content.The shear strength parameter has the spatial distribution characteristics.The appearance of cracks and staggered floor is due to the distribution and change of shear strength parameters.