The Influence of Rock Mass Disturbance on Surface Subsidence in Urban Areas

This paper presents an analysis of the parameters of surface deformation prediction theory carried out for a hard coal mine in the Upper Silesian Coal Basin. Two areas of the coal mine were used as the subject of this analysis – in these areas, underground mining with roof caving was carried out in similar geological conditions for various numbers of seams, and consequently, for various rock mass disturbance rates. In order to estimate the parameters of the surface deformation prediction theory, i.e. the exploitation coefficient and the angle of the main range of influences, geodesic measurements of subsidence along the observation lines were used. The study shows that rock mass disturbance affects the values of the Knothe theory parameters and the values of the surface deformation indicators. In the case of a larger number of selected seams, the determined value of the exploitation coefficient was larger than the determined value in the case of a less disturbed rock mass. Assuming inappropriate parameters for surface subsidence prediction may cause unexpected damage to surface objects.