不同坡角下月壤滑坡机理的离散元分析

月球表面存在不少的高陡边坡,其坡度一般都大于30°,月海区可达48.9°,月陆区甚至可达55.7°,这些高陡的边坡会严重影响未来月球资源开采等活动的安全。通过引入考虑范德华力和抗转动作用的月壤微观接触模型,采用离散单元法模拟了不同坡角下的月壤滑坡试验,对滑坡过程、滑坡机理及常见的工程灾害指标进行分析。结果表明:坡后体积一定,流滑距离会随着初始坡角的增大而增大;最终倾角几乎不受初始坡角的影响;滑坡过程中,当切坡倾角低于60°时,滑坡过程呈现流动状态,高于60°时,滑坡过程呈现类崩塌状态;滑体的最大速度随初始坡角的增大呈现抛物线式增长。

Discrete element analysis of landslide mechanism on lunar soil induced by different slope angles

There are many high and steep slopes on the Moon, whose slope angles are usually larger than 30°. The maximum slope angle may reach 48.9° on the lunar mare and 55.7° on the lunar highland. These steep slopes will seriously affect the safety of the future lunar exploitation , such as the in situ resource utilization. By implanting a new microscopic model considering rolling resistance and van der Waals forces, two-dimensional simulations of lunar soil landslide tests were carried out at different initial slope angles using discrete elemt method. The effects of the initial slope angle on landslide mechanism and engineering disaster indexes were analyzed. The results show that with a certain rear slope volume, the maximum flow distance increases with the increase of the initial cut slope angle while the final stable slope angle seems unaffected by the initial cut slope angle. During the landslide process, the slope with slope angle lower than 60° mainly fails in a flow mode while the slope fails in a collapse mode when the slope angle is larger than 60°. In addition, the maximum slide speed increases in a parabolic ways with the increase of initial slope angle.