shear capacity of the foundation piles supporting
the building through the hydraulic fills of the
Cape Town Foreshore area.
The solution comprised the in-situ construction
and sinking of eight reinforced concrete caissons
down to the soft rock at 13 – 14m, four for the
central core and one each for the corner cores to
the 5,000m2 floorplate.
The caissons were gravity-sunken down to
bedrock level at depth by means of excavating
out the sand inside and extensive water jetting.
Christiaan Barnard
The caissons sealed on the soft rock reasonably
well, allowing for the water inside to be pumped
out for the casting of the bases and subsequent
filling with hydraulic sand.
The shape of the building as well as earthquake
considerations ruled out the provision of permanent
movement joints. Temporary half-joints with rods
and pockets were used that could accommodate
shrinkage movement of the reinforced hospital
floors as well as the post-tensioned parking
levels while maintaining structural integrity and
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