Page 209 - Numerical Analysis and Modelling in Geomechanics

190 ANNAMARIA CIVIDINI AND GIANCARLO GIODA

Figure 6.15 Horizontal convergence vs time data measured at different tunnel sections
(after [25]).
Table 6.1 Distance from the tunnel entrance (Italian side) and depth of cover of the
various sections.

Among the performed in situ measurements, the inward displacements of the
tunnel walls (convergence) were adopted as input data for the back analyses.
These measurements were carried out at various sections along the tunnel axis
and, as usual, along different directions.
The input data of a back analysis should depend on the overall behaviour of
the rock mass and should not be influenced by local effects such as, for instance,
the movements of rock wedges that could develop in the vicinity of the tunnel