人工土固结过程中微观结构效应研究

通过定量分析固结人工土的微观结构,研究非黏土矿物与黏土矿物对土体微观结构(颗粒和孔隙)变化的影响。经ESEM图片比对分析后发现:非黏土矿物长石试样颗粒较大,粒间大多以面-面连接,结构较致密,加载后,大颗粒碎散成小颗粒,颗粒平均粒径减小,圆形度提高,颗粒定向性变化较大而其分布分维数呈现下降趋势;黏土矿物高岭土试样颗粒较小,粒间大多以边-边、边-面连接,孔隙较多,加载后,团聚现象明显致使颗粒平均粒径增大,圆形度降低,孔隙也逐渐向团聚单元体内部孔隙转变,在加载初期(p<100 kPa),颗粒与孔隙的定向概率熵与分布分维数均明显下降,之后趋于稳定。

MICROSTRUCTURE EFFECTS OF ARTIFICIAL SOIL IN THE CONSOLIDATION PROCESS

The effect on the soil microstructure(grain and pore) of non-clay on clay minerals and clay minerals is analyzed quantitatively by studying the artificial soil’s microstructure in the consolidation process.The ESEM image analysis found that the non-clay minerals feldspar sample has the following characteristics including larger particles,face to face connection mostly with dense structure.After loaded large particles shattered into small particles,particle mean diameter decreases,increases,the particles directional change greatly and its distribution fractal dimension shows a downward trend.However,clay mineral kaolin sample has smaller particles,which are connected with edge to edge or edge to face with more pore.After loaded,agglomeration significantly causes the average granule diameter to increase,the circularity reduce,pore also gradually change to internal porosity of agglomeration unit,in the early stage of loading(p<100 kPa),directional probability entropy and fractal of particle and pore are significantly decreased,then tends to be stable.