At 100m x 100m per bunker, these structures are incredibly large and feature a roof that is suspended 18m above the base of the tank. “This was a very complex build and we considered various approaches for its construction. Using formwork and building from the bottom up was just not feasible, especially considering the vast number of materials needed to be lifted 18m off the ground,” says Brits.
To overcome this problem, Brits and his team along with OTMS Co. developed a new method cast concrete, using formworks that are attached to the top of the columns and can slide across them. Using this method, they were then able to cast a slab in about 5-7 days, this is extremely fast compared to any other method.
“These forms are complex, high-risk elements and we needed to use CAD and Clash detection in Navisworks to develop these flying shutters that made this project possible,” says Brits. Notwithstanding the fact that this project required slabs to be poured 18 meters up in the air whilst ensure that the tall slender columns are kept stable against any sway or movement.
At roughly 50 ton per bay, one wrong move would spell disaster for a project of this nature. Brits says that risk management was of paramount importance especially considering the construction conditions and the fact that the wet concrete hangs off the collars attached only by friction.