Geotechnische Modellvorstellungen zur Abschätzung von Gefährdungsbereichen des Altbergbaus und Schachtschutzbereichen im Aachener Steinkohlenrevier

Before industrial revolution in the 19th century, mining activity concentrated on near surface coal and ore deposits. In the hard coal mining district of Aachen in close vicinity of the river “Wurm”, near surface hard coal has been mined in an area of about 19 km². Shallow mining dates back to at least the 12th century in this district. The ancient mines only reached depths of about 40 m below surface. Nowadays, collapse features still occur in irregular intervals above such shallow mining hollows and shafts, being hazardous to infrastructure and human life. The hard rock consisting of Carboniferous mudstones and sandstones of low to medium strength is covered by clayey to sandy Tertiary sediments, Quarternary sediments of the river Maas and Loess/Loessloam on top. The thickness of the soil overburden in most cases roughly varies between 15 and 25 m. In recent years, intensive field investigations of collapse features were performed. Based on these investigations, a soilmechanical model of the collapse mechanisms in the soil overburden was developed. This new model allows for the prediction of the maximum width of collapse features depending on the characteristics of the soil overburden; these soil characteristics have been neglected in the design of hazard zones in the hard coal mining district up to now. New formulas for the estimation of hazard zones are elaborated. The results of this thesis will be a basis for an efficient future risk management in the mining district of Aachen and later maybe also in other post mining regions