Abstract
This research examined the pull-out resistance mechanism using a different form geogrid by carrying out a series of pull-out test, and investigating the influence of arch action on a test result. Furthermore, the increase of the pull-out force by arch action was presumed by carrying out pull-out tests which changed the length of pull-out box. As a result, it turned out that pull-out resistance mechanism is based on the form of geogrid, and pull-out resistance of geogrids which have rough surface and small aperture is overestimated because of the influence of arch action. On the other hand, in the case of HDPE the influence of arch action is small, since pull-out resistance is mainly passive pressure which was occurred by ribs.
