This paper summarizes the modelling of rock structure at the scale of the in-situ engineering rock mass of interest, based on the synergistic combination of TLS, digital photogrammetry, and precise RTK-GPS surveying. The distinctive features of the approach are:
all data are referenced in a common 3D Cartesian coordinate system;
near-continuous coverage of a project site resulting from the registration of remote sensing datasets collected from multiple scan-positions;
creation of high-resolution, photo-realistic, true colour 3D terrain models (point cloud or mesh) to facilitate interpretations and digital measurements of fractured rock masses, especially their structural geological patterns.
In the context of rock engineering, principles and procedures have been well established (e.g. Goodman 1989, Hudson 1993, Hudson & Harrison 1997). For any practical rock mechanics or rock engineering the key issue is the generation of adequate and accurate input data which we need in analyses and design techniques. Over the last 15 years, several advanced approaches have contributed to site characterization. Hudson and Cosgrove (e.g. Hudson & Cosgrove 1997, Hudson & Cosgrove 2006, Cosgrove 2009, and Hudson et al. 2011) have integrated structural geology and engineering rock mechanics, which greatly improves rock mechanics characterization.
The recent advances to geomatics technologies enable full-scale in situ rock structure modelling for capturing, processing and extracting relevant fracture data and measurements from digital geological outcrops (e.g. Strouth et al. 2006, Decker & Dove 2008, Fekete et al. 2010, Liu & Kieffer 2011, 2012). Results from these modelling procedures show that digital terrain models facilitate unbiased and confident measurements of rock mass structures with unprecedented accuracy and resolution. The aim of this paper is to summarize our actual practices involved with using terrestrial laser scanning (TLS), digital photogrammetry, and precise real time kinematic (RTK) – global positioning system (GPS) surveying in characterizing rock mass structures.