High geogrid-reinforced soil retaining walls for a new airport

At the "Fujisan-Shizuoka Airport", which is now under construction, two high geogrid-reinforced soil retaining walls were constructed to preserve natural environment consisting of steep swamp areas in front of the walls. These areas are to be buried in the backfill if gentle-sloped embankments were constructed. The height of the walls is 1.1 m and 16.7 m. As the walls support the east side of the runway of the airport, it is required to ensure minimum residual displacements at the crest of the walls. A sufficient high seismic stability is another important design factor. To these ends, well-graded gravelly soil was selected as the backfill and the backfill was compacted very well to an average degree of compaction higher than 95%. The deformations of the walls under and after construction were monitored, which showed very small instantaneous and post-construction residual deformations of the walls. The recorded tensile strains in the geogrid also indicated a high stability of the walls.