A Comprehensive Method for Similarity Evaluation in Discrete Fracture Network Modeling of Jointed Rock Masses

To verify the accuracy and rationality of discrete fracture network modeling, a comprehensive method for evaluating the similarity between two-dimensional fracture maps is proposed in this study. Five evaluation indicators for two-dimensional discrete fracture networks are proposed, including spacing, length, angle, position, and density of rock fractures. Based on the quantitative characteristics of each indicator, methods for evaluating data distribution similarity based on the Wasserstein distance function and matrix similarity based on vector cosine values are proposed. Considering the grouping characteristics of trace lines that are neglected in existing similarity systems, the similarity between each indicator is calculated based on the grouping matching of trace line maps. This achieves the comprehensive calculation of grouping similarity and overall similarity indicators. The importance and size effects of indicators are discussed through fracture model examples. The results show that the indicators of grouping similarity are more rigorous and suitable for engineering modeling with strict requirements compared to those for overall similarity. The proposed method effectively alleviates the difficulty of comprehensive distribution similarity evaluation and achieves a more objective similarity evaluation of position and density indicators. Finally, the established similarity evaluation system is applied to real tunnel construction in Hebei Province, China, providing application value for the accuracy of fracture modeling in practical engineering.