An SA consortium has won a tender to participate in the construction of the UK's new Antarctic research station, Halley VI. Situated in the coldest, windiest and most remote place on earth, it has been billed as the world's most challenging construction project.
The consortium - comprising Cape companies Petrel Engineering and MMS Technologies, as well as Pretoria-based Outsite - will do the steelwork, external cladding and project management on the 20m project.
"Cape Town's proximity to Antarctica and the expertise of SA companies are the reasons we were invited by the British Antarctic Survey (BAS) to tender," says Petrel MD Michael Franzen.
"Halley VI must be able to withstand enormous stresses - winds of up to 200 km/h and temperatures of minus 50C," says Franzen.
In addition it will be built on an ice shelf 150 m thick, from which icebergs break off at intervals; there are fears that the ice on which the current station sits could break off within the next decade.
Halley VI's predecessors (I-IV) were buried by snow and ice, so the new station will be elevated on ski-based hydraulic legs which lift up to avoid the snow. The skis make it possible to relocate the station inland, depending on the movement of the ice shelf.
Winter darkness and a frozen sea complicate an already difficult project. Access to the region is possible only between December and March. "The challenge will be building the structures for the eight modules in time for delivery in early December," says Franzen.
The modules, each 10m wide, 20m long and about 10m tall, will be constructed from steel that is strong and flexible enough to withstand the enormous environmental pressures. "At those temperatures, ordinary steel becomes brittle, so we have to build differently."
In addition, the steel and the insulated glass fibre cladding have to fit perfectly - the tough conditions will not tolerate friction. Indeed, every component in the station, from the energy unit to the waste disposal unit, must fit like a cork in a bottle of red wine.
This month Petrel and MMS began trial assemblies of the steel structure and the glass fibre insulation panels. "To minimise time and labour in Antarctica we will subassemble the modules at Cape Town harbour, to a maximum weight of 9 t," says Franzen. "The maximum weight is critical - anything more may cause the ice to break."
For BAS, which discovered the hole in the ozone layer above Antarctica in 1985, the new base is critical to its continuing research into ozone depletion, climate change, atmospheric pollution and changing sea levels.
Financial Mail
Publisher: I-Net Bridge
Source: I-Net Bridge
