St. Maur – Créteil station is a key component of the ambitious project to extend Parisian metro lines into the suburbs of the French capital. As part of the new Line 15, this station stands out as the deepest in France, reaching 52 meters below ground. A columnless roof structure was desired for the station’s main entrance hall, leading to the selection of a spoke-wheel design supported by five columns.
A significant challenge in this design was the polygonal cross-section of the circular compression ring, aggravated by the eccentric vertical placement of cables, which resulted in high torsion forces. Originally, the inner circular acoustic panels were to support the PTFE membrane, which was only tensioned in a radial direction. However, the dome roof’s flat silhouette posed a risk of water ponding on the membrane. To address this issue, we proposed modifying the membrane’s support conditions by using the cables to span mainly tangentially to create a steeper valley, allowing better water flow and resolving the ponding problem.
