New FHWA Document: Geosynthetic Reinforced Soil Integrated Bridge System Interim Implementation Guide

GRS Bridge Abutment

GRS Bridge Abutment

The FHWA Turner-Fairbanks Highway Research Center has issued a document to provide interim guidance on the implementation of Geosynthetic Reinforced Soil or GRS Bridge Systems. From the foreward:

Geosynthetic Reinforced Soil (GRS) technology consists of closely-spaced layers of geosynthetic reinforcement and compacted granular fill material. GRS has been used for a variety of earthwork applications since the U.S. Forest Service first used it to build walls for roads in steep mountain terrain in the 1970s. Since then, the technology has evolved into the GRS Integrated Bridge System (IBS), a fast, cost-effective method of bridge support that blends the roadway into the superstructure. GRS-IBS includes a reinforced soil foundation, a GRS abutment, and a GRS integrated approach. The application of IBS has several advantages. The system is easy to design and economically construct. It can be built in variable weather conditions with readily available labor, materials, and equipment and can easily be modified in the field. This method has significant value when employed for small, single span structures meeting the criteria described in this report.

As a result of the demonstrated performance of GRS-IBS, the technology was selected for the Federal Highway Administration’s (FHWA) Every Day Counts initiative, aimed at accelerating implementation of proven, market-ready technologies. This report is the second in a two-part series and provides the background and other supporting information to substantiate the design method of GRS-IBS. The first document is a manual covering the design and construction of GRS-IBS. This two-part document series designs GRS as a composite material with known and predictable performance and deformations. Both documents are a collaboration between many disciplines within FHWA: geotechnical, structural, hydraulic, maintenance, and pavement engineering.

[Source: FHWA via News. Image: FHWA]