Business Society News on August 13th: The "membrane" that cars can't crush
The outer membrane structure of the "Water Cube" adopts ETFE material, which is lightweight but has an unimaginable strength. After being inflated, it can withstand a car rolling over it; pictures of steel structure factory are available. The membrane has excellent extensibility and obvious fireproof and heat-resistant properties. It can be stretched to three to four times its original length without breaking. Its ignition point is above 715 degrees Celsius to burn a hole, but it does not spread, nor does it produce smoke or falling combustion debris. This is the first fully enclosed sports arena in the world to use large-scale ETFE.
The "Water Cube" that breathes
The roof of the "Water Cube" has natural exhaust fans, and there are also openings at the bottom between the two layers of the membrane structure, equaling eight natural ventilation ports. Air enters and exits through the cavity of the roof, thus dissipating the heat within the building space.
All air cushions required for the outer membrane structure must pass three inspections before becoming a part of the "Water Cube". The first inspection occurs at the processing plant, mainly focusing on material checks, thermal load checks, and quality appearance checks of the membrane materials. The second step involves the supervisor rechecking the entire appearance quality of the air cushions on-site, only allowing installation after passing the recheck. The final step is a comprehensive big inspection by the supervising engineer during the installation process, covering aspects such as the appearance quality, fixation, and room height of the air cushions.
The star-like "coating"
People who have visited the National Aquatics Center would not find it hard to notice that under the sunlight, the "Water Cube" has many shiny highlights, resembling stars scattered across its surface. These highlights are the coatings.
The coating is functional coating. Through the coating, the membrane structure becomes a filter for light and heat, letting in what is needed and reflecting back what is not. The coating changes the direction of light, blocking excessive light and heat outside the venue, thereby ensuring that the "Water Cube" does not become a huge "greenhouse bath" during hot weather.
The water-saving and electricity-saving "Water Cube"
The roof of the "Water Cube" covers an area of 30,000 square meters, allowing 100% collection of rainwater. It has a rainwater collection system, with the annual collected rainwater equivalent to the annual water consumption of 100 households; related technologies such as membrane structures enable full utilization of natural light, currently averaging 9.9 hours of natural light usage per day, achieving significant electricity savings.