Ground Loss

 

Assessment of Tunnel Induced Settlement Damage

 

The program is designed to analyse and determine the shape of the subsidence trough above excavations and to evaluate the damage to buildings situated in the affected area.

 

Main features
  • Subsidence trough analysis using the Volume Loss Method or classical theories (Peck, Limanov, Fazekas)
  • Shape of subsidence trough estimated using Gauss or Aversin approximation
  • Can model sequential excavation and multiple tunnel tubes
  • Determination of subsidence trough shape, settlement, gradient and horizontal strains
  • Subsidence trough analysis at ground surface or at given depth
  • Consideration of layered geological profile when using traditional methods
  • Implemented table with recommended values of VL and k when using the Volume Loss Method
  • Assessment of building damage.
  • Determination of tensile strains, gradients and local strains
  • Can analyse selected segments of buildings
  • Implemented limit values of building damage classification

 

Building damage due to tunnelling

Considerable experience with a number of shallow tunnels excavated below built-up areas allowed the elaboration of the relationship between the shape of the subsidence trough and the damage to buildings in overburden areas. The program predicts ground movements with such precision that it is now possible to use the results to estimate financial compensation for damage induced by tunneling. Its accuracy is sufficient for the preparation of contract documents and for use by contractors bidding for tunnel construction.

The program offers four types of building damage determination:

  • Evaluation of tensile failure
  • Evaluation of failure due to trough gradient
  • Evaluation of a relative deflection of buildings (hogging, sagging)
  • Evaluation of selected section of a building