On May 15, 2009, the world's longest stress-ribbon bridge opened in San Diego, California. T.Y. Lin International developed the concept for this bridge and provided initial planning studies through detailed design and resident engineering and inspection during construction. The 1000-ft crossing of Lake Hodges provides a vital connection of two separate portions of the existing Coast to Crest Trail within the San Dieguito River Valley Regional Open Space Park.
- This bridge type has only been constructed five times before in North America and it is the world’s longest stress ribbon bridge.
- The bridge features a 16-inch-thick concrete deck to span 330 feet between supports for an amazing depth to span ratio of 1:248
- The project’s construction took place around the breeding season of several endangered bird species that nest nearby.
To decide the bridge type most appropriate for the location, T.Y. Lin International evaluated the project site and the client's core values. The parameters included a provision for a crossing for bicyclists and pedestrians that protected the natural waterway and preserved the natural resources of the river valley, while protecting the sensitive lands, biological resources, and the threatened and endangered bird species that nest at the site.
Aesthetically, the stress-ribbon type prevailed as the ideal choice. Since the water level at this region of the lake fluctuates, it was important to ensure the chosen design would work well in both wet and dry conditions. The slenderness and complimentary curves of the deck blend into the site and work beautifully in both wet and dry conditions. When the lake is full, the bridge appears to "float" above the water. In dry lake conditions, the bridge appears to "nest" above the willow trees. The stress-ribbon design allowed the use of over 300-ft spans, facilitating the placement of only two piers in the lake. Since the bridge could be built using precast panels, no falsework was required. Simply put, the stress-ribbon type was the ultimate in eco-friendly design.
Complex bridge design analysis was used to model the behavior of the geometrically non-linear structure. Since the bridge was constructed segmentally, a stage construction analysis was performed to track the stresses that are locked into the different bridge components as the bridge was built.
- Orchid Award, Landscape Architecture, 2011
San Diego Architectural Foundation
- First Place, Globe Award, Bridges (Projects < $100M), 2010
American Road and Transportation Builders Association (ARTBA)
- National Honor Award, 2010
American Council of Engineering Companies (ACEC)
- Transportation Innovation Award for Alternative Modes, 2010
Women's Transportation Seminar (WTS)
- Outstanding Bridge Project, 2010
American Society of Civil Engineers (ASCE) San Diego Section
- Outstanding Civil Engineering Project Award, 2010
National Engineers Week
- Bridge Design Award, 2010
Concrete Reinforcing Steel Institute (CRSI)
- Outstanding Project Award, 2010
National Council of Structural Engineers Associations (NCSEA)
- Honor Award, 2010
American Council of Engineering Companies of California (ACEC-CA)
- Best of the Best Award, 2009
- National Design Award for Best Non-Highway Bridge Project, 2009
Precast/Prestressed Concrete Institute (PCI)
- Small Project, Best of 2009
- No. 7 in Top 10 Bridge List, 2009
Roads and Bridges
- Project of the Year, 2009
American Public Works Association (APWA) San Diego Chapter