Load Transfer Mechanism in Pull-Out Tests

This paper presents a numerical method to predict soil-geotextile interface friction parameters. A strain softening model was used to simulate the relationship between shear stress and horizontal displacement at the soil-geotextile interface. Pull-out tests were performed on two types of geotextile, with different tensile stiffnesses, embedded in a granular soil. For each geotextile, pull-out tests were performed at confining pressures of 20, 50, 100, and 200 kPa. It was found that, unless breakage of the geotextile occurs, the peak pull-out force occurs after a small displacement of the free end of the geotextile. At the peak pull-out force, the maximum shear stress occurs near the free end of the geotextile while the shear stress at the loaded end is at or near a residual value. The use of an average interface friction angle overestimates pull-out resistance. The numerical technique developed in this paper provides more accurate values for soil-geotextile interface friction parameters.