The Toranomon redevelopment includes four bridges, with the largest T-deck functioning as a 35×20 m open plaza between buildings. It uses a simply supported monocoque box girder with a folded bottom flange to efficiently handle bending and shear. The low-indeterminacy support system reduces sensitivity to differing building substructures. Piers with multi-faceted, non-standard sections are engineered for ductile behavior, limiting horizontal forces during major earthquakes. This enables exceptionally slender columns capable of resisting seismic loads up to 2G. Exposed structural steel surface eliminates the need for additional exterior finishes, lowering maintenance requirements and reducing the risk of falling objects during seismic events.

Program | Complete mission for architectural and structural design and Landscape design of footbridges
Study | 2017-2020
Execution｜2021-2024
Client｜Mori Building
Budget｜2,600,000,000yen（4 Footbridges + canopy）
Scale｜Length 19.6m, Main span 13.0m, Width 18.0/5.5/7.5m（Deck1）
Length 35.4m, Main span 34.4m, Width 18.0～20.0m（Deck2）
Length 16.6m, Main span 15.7m, Width 5.0m（Deck3）
Length 18.2m, Main span 17.2m, Width 5.0m（Deck4）
Architect & Engineer | Ney & Partners
Cooperation | Oriental Consultants
Plant Design | Green Wise
Lighting Design | Loi + Ney & Partners
Building Design | OMA NY + Kume Design
Site | Tokyo, Japan
Image credit | momoko japan