不同区域原状黄土颗粒和孔隙特征分析

The Particle and Pore Characteristics of Natural Loess in Different Regions

摘要:

研究不同区域黄土颗粒和孔隙大小、形状和排列的定量差异,针对甘肃兰州、陕西西安和山西运城的原状黄土的电镜照片进行定量分析。首先应用Autocad描绘获得颗粒和孔隙的边界,拉开各对象后填充,然后导入到图像分析软件中获得各对象的长轴,短轴、周长、面积和长轴方向角;其次应用得到的参数计算反映对象大小、形状和定向排列的定量参数;最后比较不同区域原状黄土中颗粒和孔隙的定量参数差异。结果表明:甘肃兰州黄土颗粒的平均直径最大,形状最偏离圆形,三个区域颗粒排布在空间分布均匀;甘肃兰州黄土的孔隙平均直径与陕西西安的接近,形状更偏离圆形;颗粒的平均直径接近于孔隙的平均直径,颗粒形状更接近于圆形。

Abstract:

To study the quantitative difference of particle and pore size,shape,and arrangement in the natural loess in the different geographic regions of China,scanning electron microscope analysis of undisturbed loess in Lanzhou,Xi'an,and Yuncheng were obtained.Using autocad,the boundaries of the particles and pores of the material were mapped,then the boundaries were pulled away and color coded.These objects were then imported into image analysis software to obtain the long axis,short axis,perimeter,area,and long axis direction angle of each object. Next,the resulting analysis parameters were obtained to calculate the quantitative parameters that reflect size,shape,and directional arrangement of each object.Finally,the quantitative parameters of the natural loess particle and pore from different areas were compared.The analysis results showed that the mean diameter of particles in Lanzhou is the largest and the particles in this area are the furthest from being circular.The particles of loess in the three regions are uniformly arranged in space.The mean diameter of particle pores in Lanzhou material is close to that found in Xi'an and the shape of particle is closer to a circle.The mean diameter of the particles is near to the mean diameter of pore and the shape of particles is close to a circle.