蒙脱石含量对粉质黏土填料压实和强度的影响

鉴于黏土矿物中蒙脱石的亲水性最强,开展了蒙脱石含量对粉质黏土压实及直剪强度特性影响的试验,运用凸面接触微观模型分析了蒙脱石对抗剪强度的影响机理,采用偏相关分析方法分析了影响粉质黏土抗剪强度因素的主次关系。结果表明:随着蒙脱石含量提高,粉质黏土的最大干密度呈加速减小的非线性变化趋势,最优含水率呈加速增大的非线性变化趋势;粉质黏土抗剪强度与蒙脱石含量呈负相关性,并随垂直压力增加趋于明显;饱和含水率条件下,粉质黏土摩擦角随蒙脱石含量增大呈线性减小趋势,黏聚力随蒙脱石含量增大呈线性增大趋势;影响粉质黏土抗剪强度的主导因素依次为垂直压力、含水率、蒙脱石含量、压实系数。

Influence of Montmorillonite Content on Compaction and Strength of Silty Clay Filler

In view of the strongest hydrophilicity of montmorillonite among clay minerals,an experiment was conducted to test the effect of montmorillonite clay content on the compaction and direct shear strength characteristics of silty clay.The influence mechanism of montmorillonite on shear strength was analyzed by convex contact micro model.The partial correlation analysis method was used to analyze the primary and secondary relationship of the factors affecting the shear strength of silty clay.The results show that with the increase of montmorillonite clay content,the maximum dry density and the optimum water content of silty clay shows a non-linear trend of accelerated reduction and increase.The shear strength of silty clay is negatively correlated with the content of montmorillonite clay particles,and tends to be obvious with the increase of vertical pressure.Under the condition of saturated water content,the friction angle of silty clay decreases linearly with the increase of montmorillonite clay content,and the cohesion increases linearly with the increase of montmorillonite clay content.The main factors affecting the shear strength of silty clay are vertical pressure,water content,montmorillonite content,and compaction coefficient.