Laboratory Performance Testing of Two Types of Geotextiles used in Danube Hydrotechnical Works

Abstract

The products included in the geosynthetic category (geotextiles, geogrids, geonets, geomembranes, geosynthetic clay liners, geofoam, geocells (cellular confinement) and geocomposites) have multiple civil engineering uses, being effectively used as drains and filters in civil and environmental works. The paper aims to test the performance of the geotextiles used for the ecological restoration of riverbank defences on the Danube River, between Calarasi and Braila. For this purpose, the analysed geosynthetics were subjected to hydrolysis and oxidation degradation in laboratory conditions. To evaluate the effect of the two degradation mechanisms, the specimens were subjected to tensile tests at room temperature. The three analysed parameters were tensile strength, elongation and failure mode. The results showed that the tensile strength values for the samples subjected to oxidation and hydrolysis are lower than the ones corresponding to the reference samples, while the elongation values determined after mechanical testing showed that hydrolysis influences the fibre flexibility. The failure mode of the analysed geotextiles highlighted the tendency of the samples to fail either in the calibrated area or at the grip, indicating that in use the geotextile will break in the strained region.