The new headquarters of China Central Television (CCTV) is a 234m tall building with a highly unusual shape, described as a ‘three-dimensional cranked loop’. The building is formed by two leaning towers, bent 90° at the top and bottom to form a continuous tube.
The building’s primary support is achieved through the irregular grid on its surface, a visible expression of the forces travelling through the tube structure; the smaller the diagonal pattern, the stronger the load and the greater the support.
The braced tube structure also gives the building the required robustness to withstand the likely seismic activity in the area and therefore provides an extra level of safety.
Before the two towers were linked, they were prone to independent movement from wind, and surface temperature variations because of direct sunlight. Construction issues were therefore a key consideration of the design process and it was crucial to analyse the way the structure behaved in its partially-constructed form.
The building combines administrative functions with news, broadcasting, studios and programme production. It enables the state-run television broadcaster to reach a new level of global broadcasting, expanding its current operation of 13 channels to over 200 on completion.