There are several specifications available for geosynthetic materials and applications. Here are a few of the most commonly reference specifications and organizations:
Geosynthetics used in U.S. transportation application are tested by the AASHTO/NTPEP program.
Design Manual for Segmental Retaining Walls
Specifications for geogrids used in Segmental Retaining Walls are found in the Design Manual for Segmental Retaining Walls.