Erdenetuya Gantulga2024-11-152024-11-152023-05-18https://gmitlibrary.net/handle/123456789/179Room and pillar mining is an established method used worldwide to extract coal, salt, and other minerals. Which method widespread use can be attributed to its relatively low cost, safety, and versatility in various geological conditions. The geotechnical and geomechanically aspects of optimizing pillars on unstable soil present mining engineers with significant challenges. It is essential to optimize pillars for the stability of underground mining operations. However, it is difficult to accurately foresee the behavior of weak soil and the surrounding rock mass due to its unique properties. Numerical methods can resolve these challenges by simulating the soil and rock mass behavior and assessing the pillars' stability.enThesis