Determining the stress and convergence at Beypazari trona field by three-dimensional elastic–plastic finite element analysis: A case study

In this paper, deformation and failure characteristics of the main drift, T-2000, and a roadway, T-3000 excavated for Beypazari trona (natural soda) underground mine, which is located in Ankara, Turkey, were investigated by in situ measurements and numerical analysis. T-2000 was planed as a main drift with a length of 965 m, 14° inclined and excavated with an area of 18 m2. The T-3000 roadway was driven in the trona ore body for the first stope. Load and convergence measurements were carried out at seven stations installed in main drift (T2000) and roadway (T3000). Measurement results indicate that the total convergences at all the stations were below 1% of the total gallery height and deformation rates were reduced significantly. Three-dimensional numerical modeling was performed to analyze the deformation and failure behavior of the drift for three different models using an elasto-plastic finite element method (FEM) approach considering Drucker–Prager failure criterion. The results of the numerical analyses were found to be comparable with in situ measurements.