含水量对滑动带强度影响的细观结构试验

Meso-structural experiment on influences of water content on intensity of slip zone

为深入研究含水量的变化对滑动带强度的影响,根据实际滑动带组分特征,配制不同含水量滑动带试样,运用大型多功能材料试验机进行室内试验研究。含水量变化时,对滑动带进行细观结构定性与定量分析,初步建立滑动带宏观变形与细观结构之间的联系。研究表明:随含水量增加,滑动带的强度发挥提前,强度明显降低,颗粒翻滚、旋转、定向排列的特征明显。孔隙率急剧增大,滑动带开始滑动;孔隙率增长速度变缓,说明滑动带内部薄弱部分出现微裂纹;当孔隙率突然减小,说明滑动带内某处微裂纹贯通而形成滑动面,滑动带破坏。初步说明孔隙率可以作为滑动带强度表述的定量指标。

In order to study the influences of the variation of water content on the intensity of slip zone,laboratory tests were performed by using large-scale multi-function testing machine.The samples with different water contents for the slip zone were prepared according to the characteristics of actual slip zone.With the variation of water content,the meso-structure of the slip zone was qualitatively and quantitatively analyzed,and the relation between macro-deformation and meso-structure was established.The results show that： with the increase of water content,the intensity of the slip zone acts ahead of time and obviously decreases and is characterized by particle rolling,rotating and directional arrangement.The porosity sharply increases,and the slip zone begins to slide.When the growth rate of the porosity becomes slow,it means that micro-cracks appear in the weak part of the slip zone.When it suddenly decreases,it means that micro-cracks transfixion and sliding surface are formed and the slip zone fails.The porosity can be expressed as a quantitative index for the intensity of the slip zone.