Pull-out test of interface characteristics between geogrid and sand

Abstract

In order to study the friction characteristics of the reinforcement-soil interface, the effects of normal stress, percentage of transverse ribs,.geogrid width and pull-out velocity on the interaction mechanism of reinforcement-soil interface and the forces acting on the transverse ribs of geogrid are studied by means of the middle-scale pull-out test of the bidirectional geogrid and soil. The results show that with the increase of the normal stress of the interface, the pull-out resistance of the ribs increases significantly and the pull-out displacement becomes smaller when the single-width pull-out force reaches the ultimate tensile strength of the grid. Due to the squeezing effect of sand on the geogrid, the more uniform distribution of the cross-ribs of the geogrid is, the more favorable the force of the reinforcement is; the ratio of the interfacial friction to the total pull-out force decreases with the increase of the percentage of the transverse ribs, and the pull-out force of the narrower geogrid is slightly smaller than that of the wider grid under the same pull-out displacement. The longitudinal strain of the geogrid increases first and then decreases in the length direction, and the strain peak position gradually moves away from the loading end as the pull-out force increases, which indicates that the force acting on the geogrid is the transferable and inhomogeneous during the drawing process, and the maximum value is gradually moved toward the middle of the reinforcement due to the influence of the drawing deformation of the reinforcement.