RETRACTABLE ROOF STADIUM - NARODOWY OLYMPIC STADIUM, POLAND
The retractable roof is made of a polyester membrane covered with PVC, which is flexible, long-lasting and highly transparent.
The main structure of the retractable roof consists of:
- no. 60 radial cables
- no. 1 spiral placed in the center of the structure
- no.4 supporting cables
- no.1 ring for the whole structure tensioning
The radial cables that connect the upper tension ring with the center of the structure are the main components and form the retractable roof primary structure. The membrane is connected to the cables by sliding carriages.
https://www.youtube.com/watch?v=0NTDpySxX9I

Upper tension ring during assembly

Radial cables that connect the upper tension ring to the center of the structure

Pre-stressing for membrane installation

Membrane installation