应力旋转对TJ-1模拟月壤变形特性的影响

登月成功后月球车辆的行驶以及月球基地的建设均涉及到主应力轴旋转问题,为此采用空心圆柱扭剪仪进行了两个系列的主应力轴旋转试验,以研究中主应力系数和平均应力对主应力轴旋转条件下同济一号(TJ-1)模拟月壤变形及非共轴特性的影响.试验系列I中保持平均应力、偏应力比不变,进行了不同中主应力系数的主应力轴旋转试验;系列II则是保持偏应力比、中主应力系数不变,进行了不同平均应力下的主应力轴旋转试验.结果表明中主应力系数、平均应力均对主应力轴旋转过程中TJ-1模拟月壤的变形特性影响显著.着重分析了中主应力系数、平均应力对TJ-1模拟月壤在主应力轴旋转过程中各应变分量、体变的发展趋势以及非共轴特性的影响,以期为登月成功后与月壤相关工程的设计提供参考.

Deformation behavior of TJ-1 lunar soil simulant under principal stress rotation

The principal stress rotation will be involved in these activities such as establishing lunar bases, exploring mineral resource and operating vehicles on Moon surface. Two sets of tests were performed using the hollow cylinder apparatus (HCA) at Tongji University, China to investigate the effects of principal stress rotation on the deformation behavior and non coaxiality of dry TJ1 lunar soil simulant. One set of tests enabled pure principal stress rotation at different constant levels of the intermediate stress parameter, while the deviatoric stress ratio and the intermediate stress parameter were maintained as constant with a variation of mean stress in the other set. The test results show that the intermediate stress parameter and mean stress have significant influence on deformation behavior of TJ1 lunar soil simulant under the principal stress rotation. Their effects on the development of strain components and the volumetric strain, and the non coaxiality of TJ1 lunar soil simulant were studied.