基于分形理论的疏浚淤泥固化土孔隙结构定量化研究

摘要

On the basis of analyzing the cumulative mercury injection curves and SEM photos of dredged silt soildified soil samples,the fractal dimension of pore structure of dredged silt solidified soil is calculated by using the fractal theory,and the relationship between fractal dimension and microstructure parameters, macro mechanical properties and proportion of curing agents is established.The results show that the micro pore structure of dredged silt solidified soil has obvious fractal characteristics,and its fractal dimension is between 2.8-3.2.The fractal dimension of dredged silt solidified soil has a good correlation with average pore diameter,pore surface area,bearing ratio, cohesive force,internal friction angle and the content of mineral powder.With the increasing of the fractal dimension,the average pore diameter of solidified soil and the compression index decrease,and pore surface area,bearing ratio,cohesive force and internal friction angle increase.The fractal dimension increases with the increasing of mineral powder content.The fractal dimension can be used to describe quantitatively the pore structure characteristics and mechanical properties of dredged silt solidified soil.It can also provide data support for the analysis of macro and micro characteristics of dredged silt solidified soil and the establishment of the model.%在分析疏浚淤泥固化土试样累计进汞曲线及 SEM照片的基础上,基于分形理论,求得疏浚淤泥固化土孔隙结构的分形维数,确定了分形维数与微观结构参数、宏观力学性质以及固化材料比例之间的关系.研究结果表明:疏浚淤泥固化土微观孔隙结构具有明显的分形特征,其分形维数在2.8~3.2.并且,疏浚淤泥固化土的分形维数与平均孔径、孔表面积、承载比、黏聚力、内摩擦角以及矿粉掺量之间均具有很好的相关性:分形维数越大,疏浚淤泥固化土的平均孔径越小,比表面积越大,压缩指数越小,承载比、黏聚力和内摩擦角越大;分形维数随着配比中矿粉掺量的增加逐渐增大.采用分形维数可很好地定量描述疏浚淤泥固化土孔隙结构特征及力学特性,也可为疏浚淤泥固化土宏微观特性分析及模型的建立提供数据支持.