Presented by the Australian Tunneling Society in conjunction with the Australian Geomechanics Society, this webinar will explore the use of numerical modelling of shallow tunnels to mitigate ground-borne hazards.
The presentation will include the site conditions, geological features, geotechnical/construction risks identified, outline of TBM, tunneling sequence and numerical models developed. Attendees will come away with increased understanding of how numerical models can clarify complex soil-structure interactions when a tunnel is bored in the vicinity of existing structures and assist in resolving technical problems happening at a tunneling project in the forest of buildings.
The webinar will use the case study of TBM excavations for the Metro Cityringen in Copenhagen, including 3D finite element modelling and analysis, which was undertaken to mitigate the risk of damage to existing buildings and infrastructures due to critical and challenging TBM excavations. The TBM tunnel alignment passes under historic buildings at shallow depths, which poses risks of ground subsidence.
Three-dimensional models were analysed for the stretch between Marmorkirken and Kongens Nytorv adjacent to masonry buildings dating back to the late 17th century, and the numerical models also examined the intersection between the new tunnels and the existing metro lines set only 1.50 m beneath the new ones.