Application of Distinct Element Method to analyze machine-soil interaction

采用离散元法（Distinct Element Method）对机械与土壤的相互作用进行了模拟试验，该方法是分析颗粒材料组合行为的一种很有前途的方法。结果表明，只要找到合适的参数，就能实现机械零件的合理设计。交互作用为：1。2.三轴压缩；田径鞋和泥土，3。4.轮胎磨损和土壤；5.旋转叶片与土壤；深层土壤和土壤。在此基础上，根据实际尺寸构建三维DEM程序。在三维DEM的情况下，计算时间大大增加的问题有待解决。最终报告用英文撰写，内容如下：第一章。引言，第二章。不同元素法大纲，第三章。基于DEM的沙坝贯通土体变形与阻力模拟，第4章。基于DEM的三轴压缩土体变形与应力变化模拟，第5章。基于DEM的轨道鞋土相互作用模拟，第6章。应用DEM模拟土-胎面相互作用，第七章。应用DEM模拟土壤与叶片相互作用，第8章。应用DEM模拟土与土杆之间的相互作用，第9章。土与胎耳相互作用的三维DEM模拟，第10章。结论。

Applying the Distinct Element Method, which is one of promising methods to analyze behaviors of granular material assembly, the following trials were done to simulate the interactions between machine and soil. It was shown that the rational design of machine part would be realyzed using the DEM, if the adequate parameters were found. The interactions were : 1. tri-axial compression, 2. track shoe and soil, 3. tire lug and soil, 4. rotary blade and soil, 5. subsoiler and soil. Furthermore, three-dimensional DEM program was constructed according to the real world dimension. The problem that the computation time increases very much in the case of three-dimensional DEM should be solved hereafter.The final report was written in English with the following contents :Chapter 1. Introduction, Chapter 2. Outline of Distinct Element Method, Chapter 3. Simulation of soil deformation and resistance at bar penetration by DEM, Chapter 4. Simulation of soil deformation and stress variation at 3-axial compression by DEM, Chapter 5. Simulation of track shoe-soil interaction by DEM, Chapter 6. Application of DEM to simulate interaction between soil and tire lug, Chapter 7. Application of DEM to simulate interaction between soil and rotary blade, Chapter 8. Application of DEM to simulate interaction between soil and subsoiler shank, Chapter 9. 3-dimensional DEM for simulation of interaction between soil and tire lug, Chapter 10. Conclusion.