Abstract

In this paper, three different stress paths [conventional triaxial compression (CTC), constant principal stress triaxial compression (PTC), and hydrostatic compression (HC)] are chosen to investigate the effects of stress paths on the mechanical properties of QH-E lunar soil simulant by using discrete element method simulation. The results show that under HC path, only volumetric change occurs, the volumetric strain increases quickly first, and then increases slowly and becomes more and more flat as the confining stress increased gradually to the conventional level. Under CTC and PTC paths, QH-E lunar soil simulant generates strain softening and shear dilatancy, the shear dilatancy parameters (linear shear dilatancy, residual shear dilatancy and residual shear dilatancy point) with confining stress show a good linear relationship, the value of linear shear dilatancy is larger than that of residual shear dilatancy, and the slope of regression line under CTC path is higher than that of PTC path, which indicates that the increase speed of volumetric strain under CTC path is faster than that of PTC path. Under the same confining stress, the peak deviatoric stress under CTC path is larger than that of PTC path, and a higher confining stress leads to a greater difference between CTC and PTC paths obtained the peak deviatoric stress. The results provide important information for understanding the stress path-dependent mechanical properties of lunar soil simulant.

Graphical Abstract

中文翻译：

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应力路径对QH-E月球土壤模拟物三轴压缩力学性能的DEM模拟研究

摘要

本文选择了三种不同的应力路径[常规三轴压缩（CTC），恒定主应力三轴压缩（PTC）和静水压缩（HC）]来研究应力路径对QH-E月球力学性能的影响用离散元法模拟土壤。结果表明，在HC路径下，只有体积变化发生，体积应变先迅速增加，然后缓慢增加，并随着围压逐渐增加到常规水平而变得越来越平坦。在CTC和PTC路径下，QH-E月球土壤模拟物产生了应变软化和剪胀性，带有约束应力的剪胀性参数（线性剪胀性，残余剪胀性和残余剪胀性点）显示出良好的线性关系，线性剪胀系数值大于残余剪胀系数值，CTC路径下的回归线斜率高于PTC路径，表明CTC路径下的体积应变增加速度快于PTC。路径。在相同的限制应力下，CTC路径下的峰值偏应力比PTC路径大，而较高的限制应力导致CTC和PTC路径之间的差异更大。研究结果为了解月土模拟物的应力路径相关力学性能提供了重要信息。这表明CTC路径下体积应变的增加速度快于PTC路径。在相同的约束应力下，CTC路径下的峰值偏应力大于PTC路径，较高的约束应力导致CTC和PTC路径之间的差异更大。研究结果为了解月土模拟物的应力路径相关力学性能提供了重要信息。这表明CTC路径下体积应变的增加速度快于PTC路径。在相同的约束应力下，CTC路径下的峰值偏应力大于PTC路径，较高的约束应力导致CTC和PTC路径之间的差异更大。研究结果为了解月土模拟物的应力路径相关力学性能提供了重要信息。

图形概要