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

W.A. Peck, D.P Sainsbury and M.F. Lee


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.