Stress-and-strain state of rock mass around the working behind the longwall face

Abstract

The most important task facing Ukraine’s coal industry is to ensure the operational state of mine workings. The aim of the investigation presented in this paper is to study the changes in geomechanical environment conditions around the development working at the site of its transition to the longwall face supported area. The investigation was carried out on the basis of the finite-element method. The simulation results proved that in case of supporting the developments behind the longwall, localization of maximum stress and the type of the volumetric strain state in the regular roof, hanging up at the boundary with the worked out areas, is determined by the protective face side pack rigidity. The area of maximum stress formation in the main roof indicates the place of its destruction and defines the protected working stability. The investigation determined the application sphere for induced caving in of the main roof.