Over the past seven months, the Geosynthetic Institute (GSI) has been working with the Florida Department of Transportation to conduct tests on five different commercially available geotextiles used in the construction of GGFMs. As of the beginning of 2021, we have created a new specification for this application. The result of our efforts can be found on our website (https://geosynthetic-institute.org) under specifications entitled GRI Standard GT16 " Specification for Test Methods, Properties and Frequencies of Geotextile Grout Filled Mattresses (GGFM). " The specification is a template of required properties for a manufacturer to meet or exceed. If a geotextile used for this application does indeed meet the requirements, it should function well over time as a GGFM. The properties listed in the specification were obtained by testing multiple commercially available products according to the latest standard test methods. The unique aspect of this specification in comparison to other specifications is the added emphasis on strip tensile testing rather than wide-width testing and percent open area (POA) testing in addition to the requirement for long-term performance testing regarding ultraviolet ray durability. We believe that this new specification is a step forward for this technology. It provides clear instructions on the intent and performance of GGFMs. The new specification can also be used to support the costing of a project, minimize risk and improve efficiency by allowing a manufacturer to inventory material. Perhaps you will consider using it on your next GGFM project. G FIGURE 1 GGFM being filled incrementally. Courtesy of HUESKER FIGURE 2 Cross-section schematic of GGFM. Courtesy of HUESKER FIGURE 3 Five geotextiles with one-ply construction of GGFM. Note the similar geometry from five different manufacturers. FIGURE 4 GGFM under a pier after three years of service. Courtesy of HUESKER >> For more, search GSI at www.GeosyntheticsMagazine.com. www.GeosyntheticsMagazine.com 41https://www.geosynthetic-institute.org http://www.GeosyntheticsMagazine.com http://www.GeosyntheticsMagazine.com