Structural Domain Identification by Fracture Orientation and Fracture Density in Rock Mass

  • QuocPhi, N.
  • SangGi, H.
  • TruongThanh, P.
  • Phuong, N.


A structural domain characterizes a volume of rock mass with similar rock properties, their strength characteristics, fracture orientations and the rock type. The identification of structural domains allows a better understanding of geologic structure and the potential failure of rock blocks. For failures in rock mass, geologic structure plays an important role that controls the sliding and falling of rock blocks, hence structural domains should be identified to analyse the mode and the mechanism of failure model. In this paper, two approaches are used to divide fracture pattern of rockmass into homogeneous domains: Stereonet correlation and fracture density analysis. The stereonet plots of fracture frequencies represented as poles at adjacent sections are used to calculate correlation coefficient to quantify the degree of similarity. Fracture domain boundaries were established wherever the correlation coefficient is low. The fracture density analysis is also performed along adjacent sections of reference line to track for the similarity of Rock Quality Designation (RQD) values. The change in RQD values indicates the change of fracture domains.