Abstract

Application of numerical modeling in civil and mining engineering projects not only increases the effectiveness of analysis but also improves the results of the analysis. However, due to complexity of model generation and analysis, it still is a time consuming process. The finite element method requires a discretization, or a mesh, to solve the partial differential equations representing the problem. The finer and denser is the mesh, the more time and computer memory consuming is the analysis. Therefore, one of possible solutions is to simplify the analysis by reducing the mesh density while maintaining the quality of solution. Previously, with help of a cost function, a framework was introduced for mesh optimization considering the geometries of excavations only. From the current research, the optimization strategy is improved by including the effect of geologic features represented by rock properties. Among different rock properties, Young’s modulus (E) and Poisson’s ratio (µ) were considered. The effect of each of these properties on the mesh optimization was investigated and it was concluded that the E has the most significant effect on the results of stress analysis of dissimilar rocks. Subsequently, an expanded cost function incorporating E was formulated. Finally, an application of expanded cost function was demonstrated using a few representation case studies.