State/county bridge building with geosynthetics wins award

Among recent recipients of the Federal Highway Administration’s (FHWA) Accelerated Innovation Deployment (AID) awards is the Arizona Department of Transportation in conjunction with Mohave County.

These state and local state agencies partnered to design and build a geosynthetic-reinforced soil–integrated bridge system (GRS–IBS)* project on Oatman Highway in northwestern Arizona.

The bridge now spans the Sacramento Wash to provide a low-tech, low-cost solution to flooding issues in this area.

*The geosynthetic reinforced soil–integrated bridge system (GRS–IBS) is an innovation for helping reduce bridge construction time and cost Due to the ease of construction and the use of readily available equipment and geosynthetic materials, GRS-IBS projects can be built in weeks instead of months.

Originally developed by the Federal Highway Administration (FHWA) under the Bridge of the Future Initiative, GRS–IBS can help states and local public agencies meet the country’s demand for small, single-span bridges by delivering low-cost, strong, and durable structures in less construction time.

The technology consists of three main components: (1) the reinforced soil foundation, (2) the abutment, and (3) the integrated approach. Alternating layers of compacted granular fill and geosynthetic reinforcement provide support for the bridge.

The closely spaced reinforcement and granular soil create an efficient composite material that is internally stable and capable of carrying significantly higher than design bridge loads with predictable and reliable performance.

Source: FHWA’s INNOVATOR (Nov.-Dec. 2015)