shallow dolomite and has a perched water table . This presented a challenge in terms of founding conditions considering the height of the building . As a result the foundation design was first on the agenda and an end bearing piled support system was chosen early on to support the entire structure including the cellular raft foundations on various levels . A herring-bone sub-soil drainage system was installed under the approximate 5,800m 2 of basement to prevent the perched water table from reaching the underside of the cellular raft .
The superstructure was the next design element to be tackled , the length of the building from end to end was not conducive to the buildings structural longevity , so the decision was taken to split the single structure into 4 individual , free standing concrete frame structures that function independently , separated only by a 10mm construction joint . Cast in-situ slabs were chosen as the main floor design at 300mm thick , which allowed the removal of column caps and relative easing of the internal construction difficulties .
Radisson Hotel 21