post mining; room-and-pillar; longwall mining; stability; finite element model
Abstract :
[en] Wallonia and Hauts-de-France regions encounter complex developments of multi-level mining cavities that may affect the stability of shallower ones. This work focusses on an abandoned room-and-pillar quarry that extracted phosphatic chalk. On the same site, coal was mined out at depths from 200 to 750 m. To evaluate the influence of deep coal mines on the stability of shallow cavities, the geometry of created voids was modelled, integrating the mining sequence. In addition, detailed topographic and structural surveys of the chalk quarry were completed by rock mass quality assessment. Then a finite element geomechanical model combining the room-and-pillar quarry and the longwall mining was created. Specific vertical cross sections were investigated. The model revealed the progressive influence of coal mining on the room-and-pillar quarry as the surface mined out increased. These large models finally provide boundary conditions for local models in which the influence of specific parameters can be investigated.
Influence of deep coal mines on the stability of shallow cavities
Publication date :
October 2023
Event name :
15 th ISRM Congress 2023 & 72 nd Geomechanics Colloquium.
Event organizer :
Schubert & Kluckner (eds)
Event place :
Salzburg, Austria
Event date :
9-14 Octobre 2023
Audience :
International
Peer reviewed :
Peer reviewed
Development Goals :
9. Industry, innovation and infrastructure 11. Sustainable cities and communities
Research unit :
F408 - Génie Minier
Research institute :
R500 - Institut des Sciences et du Management des Risques
Name of the research project :
3789 - RISSC - Amélioration transfrontalière de la Prévention et de la Gestion des Risques du Sous-Sol engendrés par les terrains sous-Cavés - Région wallonne
