Extração automática de descontinuidades e análise de estabilidade de taludes em uma mina de calcário no município de Caçapava do Sul - RS

Abstract

In a mining activity, knowledge about geological conditions represents an important step in its process, starting even before the opening of the mine and extending until the end of the operation and closure of the mine. Rockmass commonly present themselves in a heterogeneous way and with unpredictable behavior due to the presence of discontinuities, so that the characterization and classification of these structures are of great importance for all actions to be taken in the mining process. The insertion of new technologies and methods to obtain the characteristics of these discontinuities is increasingly necessary, since they are carried out in areas where access to traditional mapping is limited and can represent a danger for the geotechnical. Given this importance, this study aimed to analyze the stability of open-pit mining slopes and calculate the safety factor in a remote way, in a limestone mining area in the interior of the municipality of Caçapava do Sul. The methodology used included obtaining a dense point cloud, through the photogrammetry process using a Remotely Piloted Aircraft (RPA). From the dense cloud, the autonomous extraction of discontinuities took place, through the Facets plug-in, present in the opensource software CloudCompare. After filtering the most important discontinuity plans, a kinematic analysis was performed in the Stereonet software to identify the occurrence of failure mechanisms, planar, wedge and toppling, in each sector of the mine. Subsequently, safety factors were calculated for each type of failure. All analyzed slopes presented a stable situation, with safety factors above one, even considering the situation of fractures filled with water. The zone with the lowest safety factor was zone north, for toppling failure, with a SF of 1.2.