Construction of Three Tanks at Moorburg Power Plant
Vattenfall, a German electric power company, is constructing a new coal-burning power plant in Hamburg. Three new ash filter tanks were built as part of the power plant.
The first tank has a height of 55m and a circumference of 70m. The tank is post-tensioned with 8 strand tendons consisting of 15 Ø 150mm² strands and 100 horizontal strand tendons consisting of 9 Ø 150mm² strands. On the whole, 45t of strand tendons were produced, supplied and installed for the 55m high tank.
The other two silos have a height of 70m and a circumference of 100m each. 282 strand tendons consisting of 12 Ø 150mm² strands, 128 strand tendons consisting of 9 Ø 150mm² strands and 24 strand tendons consisting of 5 Ø 150mm² strands with a total post-tensioning steel weight of 580t were installed in these tanks. The tendons are anchored at the exterior walls of the tanks on four buttresses, with two tendons forming a full circle and the next post-tensioning group being aligned at a displacement of 90°.
The main challenge was that the individual tendons had to be subsequently installed, post-tensioned and grouted at a height of up to 70m. Assembly was carried out on two suspended platforms, with the jacks being mounted on separate lifts. Two jacks at two opposite buttresses were used to tension full circles. The grouting of the tendons was also carried out on the suspended platforms.
Despite the fact that construction work was often obstructed by storms, the installation, post-tensioning and grouting work at the two large tanks was carried out within a very short time-span. The power plant is scheduled for completion in 2014.