The importance of geology and roof shape on the stability of shallow caverns

Geology and ground conditions are critical to the design of underground openings, but shape is also a key design parameter for assessing the long-term stability of shallow caverns and tunnels. The distinct element code UDEC has been used to assess the performance of both flat and arched-roofed shallow tunnel and cavern designs for a variety of geological settings. Three-dimensional modelling has shown that instability can develop at the intersection of flatroofed tunnels, with the greatest area of instability being associated with the flattest roof designs.