Numerical analysis and geotechnical assessment of mine scale model

Various numerical methods are available to model, simulate, analyse and interpret the results; however a major task is to select a reliable and intended tool to perform a realistic assessment of any problem. For a model to be a representative of the realistic mining scenario, a verified tool must be chosen to perform an assessment of mine roof support requirement and address the geotechnical risks associated with longwall mining. The dependable tools provide a safe working environment, increased production, efficient management of resources and reduce environmental impacts of mining. Although various methods, for example, analytical, experimental and empirical are being adopted in mining, in recent days numerical tools are becoming popular due to the advancement in computer hardware and numerical methods. Empirical rules based on past experiences do provide a general guide, however due to the heterogeneous nature of mine geology (i.e., none of the mine sites are identical), numerical simulations of mine site specific conditions would lend better insights into some underlying issues. The paper highlights the use of a continuum mechanics based tool in coal mining with a mine scale model. The continuum modelling can provide close to accurate stress fields and deformation. The paper describes the use of existing mine data to calibrate and validate the model parameters, which then are used to assess geotechnical issues related with installing a new high capacity longwall mine at the mine site. A variety of parameters, for example, chock convergences, caveability of overlying sandstones, abutment and vertical stresses have been estimated.