Author(s): Jirina Trckova
Keywords: Thermal water; Confined level; Open-pit excavation; Physical andmathematical models
Abstract: Open-pit brown-coal excavation is carried out in a coal basin with a large confined aquifer of thermal gas-bearing water. The methods of physical and mathematical modelling are utilized for assessment of open-pit bottom stability against its possible break-through owing to overpressure of this water and for prediction of geohydraulic changes in consequence of excavation. The results of model solutions are compared with the levelling measurements. Physical models proved the ability to predict deformation processes in the open-pit with sufficient accuracy. The results of interactive mathematical modelling brought new findings on stress state and deformation changes and on the possibility of rise of hydraulic failure of the openpit bottom. The model solution have become a valuable source of information which are used in the designs of preventive measures designed to ensure geotechnical security of the open-pit excavation of the coal seam and the protection of thermal gas-bearing waters.