Geosynthetic Reinforces Soil-Integrated Bridge System

EDC News http://www.fhwa.dot.gov/everydaycounts/edcnews/02052015.cfm

Geosynthetic reinforced soil-integrated bridge system technology is an Every Day Counts innovation that can help reduce bridge construction time and cost. Because they are easy to build and use common equipment and materials, GRS-IBS projects can be built in weeks instead of months.

Since GRS-IBS was first named an EDC innovation in 2010, use of the technology has expanded from mainly two counties in New York and Ohio to nearly 200 structures in 44 states. As GRS-IBS use increases, so does the range of applications.

At first, GRS-IBS structures were built on county roads with low traffic, but 14 bridges have now been built on more heavily traveled National Highway System roads. That includes twin GRS-IBS structures on I-84 near Echo, Utah, and on PR-2 near Yauco, Puerto Rico.

On the Utah project, using GRS-IBS and other accelerated bridge construction techniques saved about 7 percent over conventional construction costs, cut the project schedule from 194 to 125 days and required road closure time of just 34 hours.

Several GRS-IBS structures were designed for use in active seismic regions, including one on the Big Island of Hawaii. GRS-IBS is used on projects over waterways and on grade separation projects, including crossings over roads, rail lines, and pedestrian and bicycle trails.

Idaho Accelerates Bridge Project

The Idaho Transportation Department received an FHWA Highways for LIFE grant to use accelerated bridge construction techniques on a project to replace two bridges on State Highway 75 near Challis. Crews replaced the bridge over the East Fork and the bridge over the main channel of the Salmon River on Highway 75. They used precast concrete bridge elements to finish in one construction season.

LHTAC is bringing this new innovation to the local system!

We are excited to announce that LHTAC was able to capture some innovation dollars through FHWA and the Idaho STIC to help fund a project on the local system for Jerome County Highway District. We are working with the highway district to identify the best bridge situation to use the GRS-IBS technology. The project will be a public road over an irrigation canal for this use of innovation funds. Our intent with this innovative project is to create a list of constraints to review which help identify if a GRS-IBS type of bridge replacement could be used and then have some standard plans that could be used by the local jurisdiction with consultation with a geotechnical engineer on the specific bridge identified.

As part of our ongoing efforts to reduce the costs of projects, all bridge designs through LHTAC are now being required to analyze if a GRS-IBS type bridge could work in that specific case. Some projects have constraints that require another means of foundation and abutment. One project in eastern Idaho near Grace is designing a GRS-IBS bridge and abutments to replace a bridge that has been closed. This type of bridge was decided to be the best alternative for the site conditions.