Effect of installation damage on the behavior of a polypropylene geogrid in an aggressive environment

Abstract

This study explores the effect of installation damage on the behavior of a polypropylene geogrid in an aggressive environment, providing a more realistic assessment of the long-term product behavior under severe conditions. The study’s novelty resides in evaluating the combined effect of installation damage and chemical degradation on the geosynthetic at microscopic and macroscopic scales. To this end, experimental tests were conducted in two phases. In the first phase, a full-scale field installation test and an accelerated aging test— specifically, immersion in sulfuric acid (H₂SO₄) at a concentration of 3.1 mol/L at 80 °C—were performed separately on a virgin geogrid. In the second phase, the geogrid previously damaged under the installation test was exposed to the accelerated aging test (combined degradation). The damage sustained by the geogrid after the degradation tests was evaluated by monitoring changes in its mechanical behavior using the tensile test. In addition, differential scanning calorimetry analysis was performed to assess the evolution of the thermal and morphological properties of the polypropylene, while the surface morphology of the geogrid was examined through scanning electron microscopy. The findings demonstrated that chemical attack has a less pronounced effect on the thermal and mechanical behavior of the geogrid previously damaged during the installation process compared to the undamaged geogrid. Specifically, throughout the aging time, the reductions in tensile strength ranged from 17.59 − 26.38 % following combined degradation, compared to 27.19 − 39.75 % after the aging test (single degradation). This investigation underscores the significance of considering the combined effects of degradation agents to enhance the predictability of geosynthetics’ performance in real conditions, thereby ensuring the optimization of infrastructure longevity.