The 'Water Cube'

(BEIJING, Jan. 28) -- The predominant features of the National Aquatics Center, also known as the "Water Cube," are its bubbles, which give the whole venue a random, organic appearance. The Water Cube contains more than 3,000 air cushions inside, and 110,000 sq m of an outside membrane layer. August, when the Olympics are to be held, is the rainy season in Beijing. The noise from rain falling on the membrane layer may affect the performance of the athletes. Therefore, sound and heat insulation, as well as ventilation, were great challenges in the design of the Water Cube.

Regarding this issue, research was carried out at an acoustics laboratory at Tsinghua University, and a series of measures were put forward. Underneath the cushions, a layer of noise reduction netting was installed. And sound insulation material was hung under the ceiling to ensure good acoustic quality in the whole venue.

Furthermore, sound insulation experiments were carried out. A laboratory tower was built, and two cushions with two layers each were installed on the tower. Water was sprayed on the cushions and the volume was measured.

Based on the results of the experiments, more layers were added inside the cushion. In this way, the noise of the raindrops would have no influence on the audience and the athletes.

Moreover, sound absorption material was installed in the Water Cube, including the walls, audience stands and seats. All of these measures will prevent spectators and athletes from being distracted by noise.