Tensile performance of 3D printed geogrids: effect of geometrical configuration

Abstract

The aim of this study was to evaluate the tensile performance of additively manufactured polyethylene terephthalate glycol (PETG) geogrids, printed three-dimensionally using the material extrusion technique. The Creality Ender-3 V2 printer was employed for this purpose. The printed specimens were subjected to loading at a rate of 1 mm/min until failure occurred. The geometrical parameters investigated were the shape of the aperture (square, triangular and hexagonal), the aperture size, the rib thickness and the type of junction. The results revealed that the failure of specimens was primarily brittle and independent of any specific geometrical configuration or modifications. The initiation of failure consistently originated from the junctions. Among the specimens with typical junctions, the triaxial geogrids exhibited the highest tensile capacity; among geogrids with modified junctions, the square geogrids performed the best. The load capacity of the geogrids was found to be primarily governed by linear behaviour in terms of rib width, regardless of the aperture size or shape, whereas a non-linear regression model characterised the load–displacement curves. The results indicate that it is important to account for geometrical non-linearity in specimens with hexagonal apertures.