Résumé
Nowadays, mobility is experiencing numerous transformations driven by the need to reduce carbon footprint. The INFRAlight project aims to develop an environmentally friendly composite railway infrastructure to reduce the carbon footprint in economic development. Rails are subjected to severe natural and mechanical weather conditions such as temperature variations, relative humidity, UV radiation. Therefore, the study of durability under severe service conditions is essential to the industrial exploitation of these materials. One of the materials considered for this application is a pultruded fibre-reinforced plastic (FRP) made of polyamide 6 (PA6) and glass fibres (GF). Literature shows that the durability of pultruded composite materials is still an understudied topic. However, several studies have shown that PA6 polymers are sensitive to moisture, leading to changes in their physicochemical properties and a decrease in their mechanical properties. In this study, accelerated hygrothermal ageing at 70 °C and 80 %RH was applied to the PA6/GF pultruded composites. The results show a decrease in mechanical properties during water absorption, followed by a recovery upon drying, highlighting the reversibility of the ageing process.Viscoelastic characterisation from vibration analysis complement these results to understand the effect of moisture on the material.