Geometrization of a 3D numerical model of an underground facility based on the results of terrestrial laser scanning

The article proposes a method of combining CloudCompare, RHINO, and FLAC3D software, aimed at building numerical models of underground objects of natural or engineering origin, based on the results of measurements made using terrestrial laser scanning technology. This technology is one of the most advanced in mine survey as it enables accurate mapping of even the most complex geometries of underground facilities. This opens wide possibilities in the construction of more accurate numerical models of the behavior of the rock mass around such underground objects. The results of simulation of the behavior of the rock mass around the analyzed excavations, obtained by performing numerical calculations, allow predicting unfavorable phenomena that may occur as a result of the destruction of the rock mass and which may threaten the safety of users of underground facilities, for example, caves, tunnels, and mining excavations. In this work, we carried out measurements using a terrestrial laser scanner and obtained a “point cloud” that reproduced the geometry of the underground facility. An example is a fragment of the adit St. Johannes, which is part of the underground tourist route “Geopark” St. Johannes Mine in Krobica in Lower Silesia in Poland in the neighborhood of Gierczyn and Przecznica. In the next step, the measurement results were processed, so that it was possible to import the generated geometry into the FLAC3D software and use it to build a numerical model of the adit, based on “brick” zones. The aim of the article is to present in detail the methodology of geometrization of numerical models of underground objects with complex geometry. The author wanted the method to be as easy to use as possible, give full control over the surface structure, and not require many numerical modeling programs.