Case studies

The oversized geogrid panels were overlapped 2ft and tied together to prevent movement during backfilling. Photo courtesy of Maccaferri.
The oversized geogrid panels were overlapped 2ft and tied together to prevent movement during backfilling. Photo courtesy of Maccaferri.

  • Geotextiles enhance road performance

    Sponsored by Geosynthetic Materials Association

    Pavements in the U.S. first incorporated geotextiles beneath roads, parking lots and railroad track ballast in the 1960s. In the early 1970s, 3 million square yards of geotextiles were used in infrastructure projects. By the 2000s, more than 300 million square yards were used beneath roads throughout the world. A 2006 study by the Geosynthetic Research Institute found that 40 out of the 50 state DOTs have a specification for a separation geotextile.

    Geotextiles prevent the mixing of the fine subgrade soils with the engineered aggregate support layer. By preventing this mixing, geotextiles prevent early deterioration of roadways.

    Cost savings

    The cost of the installed separation geotextile is typically less than the cost of 1 inch of base course aggregate; separation geotextiles typically prevent contamination of several inches of base aggregate. Therefore, the benefit significantly outweighs the cost of using a separation geotextile in pavements.

    Local and state studies have proven that the use of geotextiles as separators has enhanced road performance as a result of the placement of the geotextile between the subgrade and the pavement aggregate base layer. Studies show the extended life of pavement sections that incorporate geotextiles. These studies have shown reduced long-term maintenance and reduced pavement rehabilitation costs for roads using geotextiles.