Statistical Characterization of Rock Structure using LiDAR

 

When designing with rock masses of relatively high intact strength, characterization of the geologic structure properties is a critical component to proper analysis. Data describing distributions of discontinuity orientation, length, spacing and strength for pertinent sets within the rock mass provide the basis of probabilistic models necessary for analysis. Probabilistic methods require a reasonably large sample size in order to provide reasonable estimates of inherent structural variability. The use of laser scanning, or LiDAR, technologies is commonly utilized as a high resolution survey technique but is less frequently used, in conjunction with registered high resolution digital imaging, as a tool for geotechnical data collection. This methodology can provide a cost effective and time efficient means of collecting such large data sets. A case study was carried out to evaluate the correlation between statistical characterization of discontinuity properties acquired manually in the field using oriented core and cell mapping techniques to those obtained remotely using LiDAR. The benefits and limitations of these methods are evaluated and practical recommendations are made based on results of the case study.