Evaluating the Tensile Properties of Geogrids Using the Particle Image Velocimetry Technique

Abstract

This study investigates the use of the particle image velocimetry (PIV) technique and GeoPIV-RG software to track the localized axial and lateral strain development of composite geogrid specimens in a wide-width tensile test and to evaluate the load-strain response of the composite geogrid material. The effects of strain rate on the mechanical properties of composite geogrid specimens in both the machine direction (MD) and cross-machine direction (CMD) under tension were also investigated by performing tests under three different strain rates. The aperture at the center of the test specimen was suggested as the optimum location of the geogrid specimens to accurately measure strain development. The wide-width tensile test results revealed that the stiffness of the tested composite geogrid was independent of the strain rate and was comparatively higher than the manufacturer specified values. Therefore, these test results confirm that the crosshead method underestimates the tensile properties of geosynthetics in the wide-width tensile test. The findings suggest that cost-effective geotechnical structures can be designed adopting the tensile properties obtained from the GeoPIV-RG technique instead of the crosshead method.