Evaluation of the Degradation of Polypropylene Geotextiles under Real Coastal Conditions and UV Radiation Exposure

Geotextiles are permeable polymeric fabrics used in coastal protection to allow water flow while retaining fill material. These materials are usually minimally exposed to solar radiation (UV) and other atmospheric agents, often being covered by soil or liquids. However, exposure during installation can cause degradation. This study analyzed the impacts of weathering on a polypropylene geotextile exposed to different UV radiation conditions in Natal/RN, Brazil. The samples were exposed for 29, 58, and 90 days under four conditions: on a wooden table, on beach sand, immersed in seawater, and on beach sand submerged in seawater. After exposure, tensile strength tests were conducted. The results indicated that the transverse tensile strength of the exposed samples remained within the confidence intervals of the virgin geotextile (50.92 ≤ μ ≤ 56.46 kN/m), suggesting no significant degradation during exposure. The samples immersed in seawater exhibited the lowest standard deviation in strength, with an average of 1.993 kN/m. On the other hand, the samples on beach sand submerged in seawater showed the lowest average strength, at 53.77 kN/m. In conclusion, exposure to coastal weathering during the studied periods did not significantly affect the geotextile’s integrity.