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In the construction industry, increased efforts are being made to automate production processes using industrial robots in order to increase efficiency, improve quality and optimize the use of materials. Tunnel construction is particularly suitable for the use of modern production methods, as the increased use of machines and the high repetition factor of the components used make it possible to scale production technology across project boundaries. This paper provides examples of current developments in segment production, in particular the use of industrial robots in the prefabrication of reinforcement cages and subsequent concreting. Necessary adaptations in segment design are pointed out when welded reinforcement is used, and conceivable further developments are shown. The medium‐term goal is a continuous IT‐based production control system that allows short‐term adjustments to segment production, logistics and subsequent installation in the tunnel. [ABSTRACT FROM AUTHOR]

Glacial soil deposits are present in Europe on both sides of the Alps, in Scandinavia, Northern Germany, Poland and in North America. There are typical names of the stages of the glaciation, however, the geotechnical characteristics of glacial deposits are similar in all regions; but are very heterogeneous locally. Glacial deposits extend from boulders to invisible silt particle (rock flour) and to clay particles, both of similar grain size. In this paper the focus will be on clean gravel without fines, so‐called open gravel and the challenges and solutions for tunnelling. Face support by pure bentonite slurry is insufficient in open gravel. Different techniques have been used in practice: clogging the pore channels with fines of appropriate gradation by controlling the content fines in the slurry. Use of high viscous slurry with increased clay or bentonite content. In another solution lime powder and polymers were added in the excavation chamber of an earth‐pressure shield to modify the ground. Other aspects such as muck disposal will be evaluated. [ABSTRACT FROM AUTHOR]