Researches on interacton mechanism between geogrid and sand by pull-out tests

The complicated mechanism of interaction between soils and reinforcement is the key problem in the application of geosynthetic reinforced soil engineering. Through laboratory pull-out tests, the mechanism of interaction between sand and geogrid and the factors of grid metric features influencing the pull-out resistance have been explored. This research work tentatively reveals the action mechanism of transverse ribs and longitude ribs and the influence of grid rigidity on the pull-out resistance. The results indicate that the interface friction of longitude ribs and the passive resistance of transverse ribs develop basically simultaneously when the pull-out displacement is small; while the displacement becomes larger, the longitude ribs' fricton reaches gradually the peak value, the increaseing of pull-out resistance is mostly attributed to the development of transverse ribs' resistance. The tensile modulus and the structure stiffness of geogrids are the important factors affecting the mechanical charateristics of interface between soils and reinforcement.