Tacoma Narrows Bridge

Evaluating parallel bridges through wind tunnel studies and analysis 

Shortly after opening in 1940, the original Tacoma Narrows Bridge sustained high winds leading to its spectacular collapse. Lessons learned were incorporated into a new suspension bridge at the same site in 1950. By the 1990s, increased traffic led to the need for a new adjacent and parallel bridge, with each bridge carrying traffic in a single direction. We investigated the aeroelastic stability of the proposed bridge, its potential aerodynamic effects on the 1950 bridge, and the effects of modifications planned for the 1950 bridge. The new bridge opened in 2007 and today both bridges continue to serve the area’s transportation needs well.