Durability of geogrid in a sloped reinforced soil wall after 25 years in service

The durability of geogrid reinforcement exhumed after 25 years from a sloped wall structure was examined through a comparison of the material properties of exhumed samples with technical data for the original product type. Visual and microscopic inspections found no evidence of installation damage. Analysis of strain increments in rapid loading creep tests to 10 000 h showed excellent agreement between the exhumed and original materials. The results of this study lend confidence in the use of isochronous load–strain–time data for predicting the long-term strain of geosynthetic-reinforced soil structures in design to a serviceability limit state.