Project showcase. Building the bridge of the future with GRS technology: Fid-Bau Portal

Project showcase. Building the bridge of the future with GRS technology

Build the bridge of the future better, faster, and for less money using geosynthetic-reinforced soil (GRS) technology for abutments. Instead of a conventional bridge, supported on pile-cap abutments, GRS technology uses alternating layers of compacted fill and sheets of geotextile reinforcement to provide support for the bridge. GRS abutments can be built with readily available material using common construction equipment, without the need for highly skilled labour. They are also extremely durable. Researchers at the U.S. Forest Service and the Colorado Department of Transportation (CDOT) pioneered the early development of this technology. During the summer and fall of 2005, FHWA provided guidance and abutment design plans to Defiance County, Ohio, to build the Bowman Road Bridge using GRS technology. The innovation of using GRS paid off, as Defiance County realized a cost savings of nearly 25 % on its first bridge-support project. The bridge was also built in six weeks, compared to a typical construction time of several months for a conventional bridge. For the Bowman Road Bridge, instead of using cast-in-place concrete for the abutment walls, split-face cinder blocks (modular concrete blocks) were used to face the abutment. The bridge does not have an approach slab, but rather GRS was compacted directly behind the bridge beams to form the approach way and to create a gradual transition from the roadway to the bridge. Asphalt pavement was then placed on the bridge and approach without a conventional joint system at the bridge ends. FHWA instrumented the bridge so that performance monitoring can be conducted during the next several years. Defiance County is planning to build seven more abutments this year using GRS.