Heavy traffic volume, narrow and winding road alignment, as well as hazards such as severe weather and natural forces place high demands on the safety of the Gotthard pass road. Under the leadership of the Federal Roads Office ASTRA, planners and contractors have so far managed the renovation under these difficult conditions exactly on schedule. At the same time, ASTRA’s sophisticated project management regulates the ongoing traffic flow on this important connection route between the north and south of the Alps.
Since April 2017, the renovation of the Tanzenbein galleries (middle and south sections) and Brüggwaldboden as well as the Fadegg tunnel has been underway. These structures protect road users from rockfall, landslides, and primarily avalanches. To increase the safety of the Tanzenbein gallery, the existing roof was reinforced. For this purpose, 1,900 fischer FCC-A concrete-to-concrete shear connectors, consisting of anchor rods and special nuts, were installed over an area of 250 square meters. The center-to-center spacing was 25 and 35 centimeters depending on the direction. First, the concrete workers of the responsible construction company Implenia drilled holes into the existing concrete according to specified dimensions. After careful hole cleaning, they filled these with the 2-component injection mortar FIS V. They then manually inserted the FCC-A into the injection mortar down to the bottom of the drilled hole. After a short curing time, these fasteners are fully load-bearing and now absorb tensile and shear forces occurring in the joint between old and new concrete and safely transfer them onward.