KB VT Temporary Stay Cables
for the Construction of the Tamina Bridge (Switzerland)
The construction of the 260 m spanning concrete arch has begun in spring this year. It is built by the free cantilever method using cantilever carriages starting from the abutments at both sides of the Tamina Gorge. 23 segments from the „Valens“-side and 32 segments from the „Pfäfers“-side are needed for the closure of the arch around 200 m above the ground.
The arch segments will be carried by 31 sets of temporary stay cables anchored at different levels at temporary steel pylons which will reach 100 m in height at maximum. On the rear side of the pylon a corresponding set of cables is guided to auxiliary foundation blocks which are again anchored by rock anchors transmitting the cable load into the ground. The temporary stay cables have been designed by KB VT to meet the requirements of function, installation and stressing.
Stressing is done by multi strand jacks. For one set of cables a number of up to 12 multi strand jacks will be employed at a time to be able to adjust the cable forces appropriately.
The first set of cables was stressed in May 2014. Completion of the arch is expected early 2015. All temporary means - pylons and stay cables - will be disassembled after the arch has been closed.