Role of Specimen Geometry, Soil Height, and Sleeve Length on the Pull-Out Behaviour of Geogrids

This paper examines pull-out test results of geogrid specimens embedded in a granular soil. The influence of specimen geometry, soil height and sleeve length on the pull-out force of the geogrid specimen is discussed and the results of nine pull-out tests are analysed. Soil and geogrid properties are also fully described and the soil-geogrid interaction behaviour is studied. The conclusions of this study are as follows: the pull-out tests are reproducible; the influence of the geogrid specimen length on the geogrid specimen pull-out response is a function of the density of the granular soil; the influence of the geogrid specimen width on the pull-out response of the geogrid specimens tested is minimal; the effect of the soil height above and below the geogrid specimen on the soil-geogrid interface shear resistance is minimal for the two soil heights tested; and, the placement of a 0.20 m long steel sleeve in the front wall of the pull-out box reduces the magnitude of back calculated soil-geogrid interface shear resistance because it minimizes the effects of friction that are caused by the roughness of the front wall.