模拟月壤微观结构形态的定量化研究新方法

A New Method for Experimental Investigation of Microstructure Morphology of Lunar Soil Simulant

摘要:

针对土体的微观结构测试设备价格较高、操作相对复杂以及传统的微观结构测试主要针对单一粒组进行的缺陷，以同济一号（简称TJ 1）模拟月壤为例，介绍了一种可测定由不同粒组组成的砂样微观结构参数（如长短轴比例、粗糙度）的新方法.通过电镜扫描获取TJ 1模拟月壤不同粒组颗粒的高倍清晰照片，利用AutoCAD和MATLAB软件获取各粒组的微观结构参数.采用离散元数值试验，近似确定TJ 1模拟月壤中各粒组颗粒所受接触力占所有颗粒接触力的权重，并与各粒组形态参数的平均值相结合，采用加权平均,最终获取TJ 1模拟月壤形态参数的代表值.

关键词:微观结构形态; 离散单元法; TJ 1模拟月壤; 粗糙度; 长短轴比例

Abstract:

In practice, the advanced test equipment for soil microstructure morphology are very expensive and complicated to operate. Conventional studies on microstructure morphology generally focus on sands with one single fraction. A new test method, which can derive the microstructure parameters (e.g. aspect ratio, roughness) of TJ 1 lunar soil simulant consisting of various fractions, was introduced in this paper. First, high definition images of particles in different fractions were obtained by using a scanning electron microscopy (SEM). Then the microstructure parameters of each fraction were obtained by using the AutoCAD and Matlab software. Finally, the weight of morphological parameters of each fraction were gained using the distinct element method analyses, and the corresponding representative parameters of the whole specimen were calculated by using the weighted average method.

Key words:microstructure morphology; distinct element method; TJ 1 lunar soil simulant; roughness; aspect ratio