Research on the Influence of Excavation Seams and Geological Conditions on Surface Movement and Deformation using Geomechanical Digital Models

Nowadays, the prediction of destruction and subsidence areas due to underground mining is typically carried out using two methods: experimental and phenomenological surveys. The experimental method is based on observational results and experiences from studies of destruction and subsidence in the field. Additionally, reliable experimental or analytical models can be used to forecast destruction and subsidence. Many models have been effectively applied in various countries around the world, especially in Europe. The phenomenon survey is based on the principles of equivalent material models, with the strata of destruction and subsidence mathematically described as ideal materials, adhering to the laws of continuous medium mechanics. However, the equivalent material modeling method has been of limited effectiveness to date, primarily due to the difficulty in describing the complex geological characteristics of the strata, which requires significant costs and time. In the world, there are very few cases of surface structures being located beneath underground mining areas due to good mining planning. In the Quang Ninh underground coal mines, Vietnam, the movement and deformation of the surface in the mine affect the conveyor line in the Northwest II area of Mạo Khê, the G9 Mông Dương mining area, and the -150 MK project area… Therefore, the establishment of geomechanical models combined with field monitoring methods is essential. This paper presents some results of using geomechanical models to study surface movement in underground mines.