Due to diversified topography a number of tunnels have been constructed on Slovenian motorway network
in the last 15 years after the implementation of the National motorway construction programme. 3D
displacement measurements of the primary lining has been applied as an integral part of the observational
method on all tunnel construction sites since the Golovec tunnel construction in 1997. Analysis and
interpretation of the measured displacements allow the verification of the design parameters, support
optimization and optimization of construction processes. Monitoring data from the 13 tunnels, constructed
after 1998, were collected and arranged in the database in the framework of this thesis together with face
logs. Further on, a computer code Predor (means Tunnel in Slovene) was developed for graphical
presentation and analysis of these data. Code comprises also a system for automatic handling of the
incoming data from construction sites and for the preparation of graphical reports in real time. The main
emphasis of the work was given to the analysis of measured displacements in tunnels, situated in soft
foliated rock mass of Carboniferous age (the Trojane, Golovec and Šentvid tunnels). Monitored
displacements display more or less pronounced anisotropic response in the cross section as well as in the
longitudinal section. To model the observed response, back analyses with numerical calculations suggested
very low value of shear modulus along the discontinuities. Special attention was paid to the analysis of well
documented longitudinal displacements in the excavation direction under decreasing overburden due to
anisotropy of the rock mass. It was found out that the magnitude of final measured displacements and thus
portion of pre-displacements strongly depends on the relative discontinuity orientation to the tunnel axis. A
large number of numerical simulations was performed to define the portion of pre-displacements and the
extent of pre-face domain for different discontinuity orientations and different sets of material properties of
the anisotropic rock mass. To locate the merging caverns of the Šentvid tunnel in most favourable rock
mass conditions the exploratory tunnel was constructed in the design stage and enabled 3D displacement
measurements ahead of the top heading face of the main motorway tunnel during its construction.
Extensive information about the scheme and execution of this experiment is given (no reports have been
found so far of any similar experiments). Monitored displacements were analyzed according to mapped
geological structure. Further on, the observed phenomena and the influence of the exploratory tunnel and
its position on the displacements were studied with 3D numerical calculations.
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