To make this possible, the central core of the building slants in the opposite direction to the lean of the structure, and it straightens as it grows. The building sits on top of a 7-foot-deep concrete base with a dense mesh of reinforced steel. The steel exoskeleton known as the diagrid sits above an extensive distribution of 490 piles that have been drilled 100 feet underground to accommodate the gravitational, wind and seismic pressures caused by the lean of the building.
The ground-breaking form of Capital Gate is due not only to its lean, but also to its funnel shape. The tower widens as it spirals upwards and outwards. Due to its strange design, each hotel room is unique in size and shape, with floor-to-ceiling windows that let guests soak up the best of the sweeping views of the city below.
One other notable feature of the building’s exterior is the sculptural stainless steel “splash” that flows down the front of the skyscraper. Near ground level it flows out horizontally, forming a canopy over the hotel’s entrance while also acting as a solar shield to help keep the building cool.
According to amusingplanet.com