In this article, the authors use the existing theoretical foundations and partial solutions to provide a general formula, which can be used to determine the value of horizontal deformation factor B for various applications of the Knothe theory. This applies to the calculation of surface deformation not only in the case of hard coal mining, but also in the case of salt mining by borehole. Convergence resulted from mining may cause deformations of caverns used to store liquid and gaseous fuels or the deformations related to the fluidized bed extraction. The calculations for the new analytical model are presented in the examples of the Etzel cavern (Germany) and the Upper Silesian Coal Basin (Poland). and Sroka Anton, Misa Rafał, Tajdus Krzysztof.
The research is focused on the feasibility analysis of a numerical model describing the field of strains generated by mining-induced subsidence caused by a deep underground coal extraction, which may contribute to the formation of Earth fissures. The finite elements method and Knothe’s theory were used in the research. The geomechanical modeling was applied for defining zones of strains and maximum horizontal deformations of the terrain. Knothe’s theory was employed for defining boundary conditions of the geomechanical model. The parameters of the empirical and geomechanical models were scaled out on the basis of geodetic surveys in the mining area. The results of geomechanical modeling were compared with the geodetic surveys to select the best model. The presented research confirmed high congruence between the results of modeling with the finite elements method and observations of vertical movements on the surface. The results of modeling also confirmed the assumed highest stress in areas where earth fissures were observed. The proposed solution may be a new research tool applicable to areas where earth fissures potentially occur. and Malinowska Agnieszka A., Misa Rafał, Tajduś Krzysztof.