With the fast pace of global urbanization and economic growth the demand for faster and more reliable transportation routes has seen an enormous increase over the last few decades. One of the biggest parts of the progress in land transportation can easily be addressed to the increased construction of tunnels which connect cities and important economic centres via the shortest possible route. This means that the engineers responsible for the construction of these tunnels are often confronted with demanding geological and constructional conditions, which include the construction of shallow tunnels with low overburden.
The instability during the construction and the surface settlements due to excavation are in the case of shallow tunnels greatly increased and they represent a great engineering challenge. For this purpose, we have seen many different tunnel excavation methods emerge worldwide, which are also the central part of this assignment. For the practical part of this assignment we will have a look at the recent construction of the north portal of the Maribor-Šentilj railway tunnel, which includes many of the difficulties discussed in this paper. Finally, we will reconsider some of the methods used in the mentioned practical case to see if the construction methods were really the best possible for the given case and if there is room for possible improvement.
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