A Multivariate Technique for Evaluating the Statistical Homogeneity of Jointed Rock Masses

Various approaches have been developed for identifying statistically homogeneous regions or structural domains in a jointed rock mass based on joint orientations or the other joint parameters; however, few studies have been conducted by integrating both. In this paper, nine parameters are considered for this identification, namely: orientation, spacing, aperture, roughness, trace length, trace type, filling, groundwater condition, and weathering. A statistical parameter, known as the correlation coefficient, is used to quantify the degree of the similarity between the joint parameters collected from four adjacent adits at the Songta dam site on the upper reaches of the Nu River in southwest China. Based on the analytic hierarchy process, the weights of the parameters are obtained. The overall homogeneity of the rock mass around the studied regions is determined based on the homogeneity index.