Architect and Builder April/May 2019 | Page 70

a wide publically accessed double volume route through the podium from the south to the north, allowing movement to and from the access road and platform as well as any future development to the north from the southern public edge. The authors of the precinct guidelines had always intended that the building envisaged for this particular site would be significantly larger than all of the others. Dealing with this large scale in the precinct became one of the principal challenges. The extensive use of glazing resulted in not only magnificent views from all of the hotel rooms and apartments but also allowed for the opportunity to highlight the structural components beneath. This horizontal and vertical expression resulted in a rich articulation of the façade and a clear expression of the various accommodations and ancillary spaces. This was further refined and reinforced through the careful choice of colour and shade. Despite its size the building sits comfortably among its neighbours in this exciting and developing precinct. Structural Engineering One of the main engineering challenges Devilliers Consulting had to deal with during construction of the project was the excavation and construction of the basement below sea level with a canal connected to the sea directly adjacent to the site. The building is over 200m long with a footprint of just over 10,000m 2 which translates to about 57,000m 3 of excavated material. Water is collected in a drainage layer connected to a sump from where the water is permanently pumped out to keep the basement from flooding. The building is founded on piles. The old sea culvert, built to supply cooling water to the old Cape Town power station, runs diagonally across the site. A series of spreader beams onto piles either side had to be introduced to span across the remains of this 8m wide culvert to allow for columns to be constructed on grid above. In addition to these challenges, two levels of transfer beams had to be introduced to cater for the different column grids of the different usages at various levels. 70 The Yacht Club