一种微结构颗粒体分布特征的分析方法  

A method for analyzing distribution characteristics of microstructural particle congeries

作　　者：李顺群[1,2] 冯望[1] 王英红[3] 

机构地区：[1]天津城市建设学院土木工程系,天津300384 [2]天津城市建设学院天津市软土特性与工程环境重点实验室,天津300384 [3]天津城市建设学院电子与信息工程系,天津300384

出　　处：《岩土力学》2013年第3期731-736,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51178290);教育部科学技术研究重点项目(No.210004);天津市自然科学基金项目(No.11JCYBJC02900);天津市科技支撑重大项目(No.11ZCZDSF04800)

摘　　要：在扫描电镜法(SEM)图像二值化基础上,建立了以颗粒体面积为变量的面积累计曲线表示方法,进而建立了该曲线的曲率系数和颗粒体面积分布特点的不均匀系数。基于瓜州砂质粉土和天津黏土的SEM图像,分析了不同面积比对应的颗粒体特征。研究表明,砂质粉土和黏土的颗粒体面积累计曲线、曲率系数和不均匀系数具有明显的差异性。砂质粉土的颗粒体面积累计曲线是一条平滑的曲线,表现为不良级配土的粒径分布特点;而黏土的颗粒体面积累计曲线具有明显的台阶,表现为某粒组缺失的粒径分布特点。另外,砂质粉土的颗粒体面积累计曲线曲率系数和不均匀系数均明显大于黏土的对应系数。该分析方法可以用来量化不同土的SEM照片之间的差异,从而为岩土微结构的定量化研究提供了一条新的思路。Based on the binary SEM image, a method to express the magnitude of particle congeries area accumulation versus the corresponding area was constructed. Afterward, the definitions of the curvature coefficient and the nonuniformity coefficient of the aforementioned curve were established in order to study the features of the curve for different types of soils. For different area ratios, the proposed method were utilized to discuss the distribution characteristic of particle congeries figured in the SEM photos respectively for Guazhou arenaceous silt and Tianjin clay successfully. The study shows that the area accumulation curves, the curvature coefficients and the nonuniformity coefficients of the silt are significantly different from that of the clay. The curves for the arenaceous silt are smoother than that for the clay and have the trait of the grading curves for the poorly graded soils. Whereas, the curves for the clay exhibit obvious multistep, namely have the feature of grading curves for the soils with certain particle lost. Furthermore, the curvature coefficient and the nonuniformity coefficient of the arenaceous silt are larger than that of the clay. The suggested technique is a new means to evaluate microstructure in soil mechanics and can be employed to quantitatively analyze the difference between SEM images for diverse soils.

关 键 词：微结构 砂质粉土 黏土 面积累计曲线 曲率系数 不均匀系数 

分 类 号：TU411.92[建筑科学—岩土工程]