OMNNI’s structural engineers recently completed the design of two bridge replacement projects in Dodge County using a technology new to Wisconsin called Geosynthetic Reinforced Soil-Integrated Bridge System (GRS-IBS). This technology was developed by the Federal Highway Administration (FHWA) as part of the Bridge of the Future initiative. On small, single-span bridges located over low-flow waterways, this innovative system helps reduce construction time and cost, allowing a bridge to be built in weeks instead of months.
With fewer federal funds available to assist local governments in the replacement of deteriorating bridges, Dodge County looked for new and innovative ways to replace their deteriorating bridges. They learned about the new technology for geosynthetic reinforced soil – integrated bridge system construction for bridges and contracted with OMNNI Associates to design replacement bridges for the CTH KW bridge over Pratt Creek and the CTH S bridge over Shaw Brook using the new technology. Only one other bridge has been constructed using this technology in Wisconsin.
GRS is an engineered fill of closely spaced alternating layers of compacted fill and geosynthetic reinforcement that eliminates the need for traditional concrete abutments. IBS is a method of bridge support that blends the roadway into the superstructure using GRS technology. The integrated system creates a transition area that allows for uniform settlement between the bridge substructure and the roadway approach, resulting in a smoother bridge approach.
The CTH KW and CTH S Bridge were honored with both the State and National “Project of the Year” awards in the transportation category of less than $5 million.
The CTH KW bridge project was honored with a first place award by the WisDOT for “Excellence in Highway Design” in the Local Program Design category.
Article by Kristofer Olson, P.E. in Structure magazine.
Check out this video promoting the new technology created by WisDOT
FHWA: GRS-IBS Facts