This study focuses on bio-based natural fiber-reinforced polymer composites (NFRPCs). In this work, bio-polybutylene succinate (bio-PBS) reinforced with hemp fibers (HF) varying at 10 wt%, 20 wt%, and 30 wt% were developed via microwave-assisted compression moulding (MACM) technique. The mechanical properties, crystalline properties, dynamic mechanical analysis, and soil degradation behaviour of these composites were analysed. The study demonstrated that composites with 30 wt% hemp fiber content exhibited the most optimal mechanical properties, with crystallinity increasing by 22%. These composites achieved the highest storage modulus of 13,349 MPa, while their loss modulus was found to be 110% higher compared to neat bio-PBS. Additionally, soil burial experiments revealed that the 30 wt% HF/bio-PBS composites underwent the greatest weight loss after 60 days of soil exposure, indicating superior biodegradability compared to the pure bio-PBS matrix. The work further concluded that hemp fiber-reinforced bio-PBS composites showcased improved mechanical performance, crystallinity, biodegradability, and processing characteristics, surpassing other bio-composite alternatives.

Reinforcement of soils with fibers generally increases the mechanical properties of the fiber-reinforced soil (FRS) system. However, published literature is limited to investigating the undrained response of clay and synthetic fibers, with few studies targeting natural clay and natural fibers under drained conditions. There is a need to study the response of fiber-reinforced clay systems under drained conditions to assess long-term stability. This paper investigated the drained shear strength and durability of clays reinforced with natural hemp fibers using isotropically consolidated drained triaxial tests, in which the fiber content, confining pressure, and compaction water content were varied. Results showed that the incorporation of hemp fibers improved the deviatoric stress at failure by up to 60%, which increased the drained cohesion and friction angle of the FRS by 7-10 kPa and 3-7 degrees, respectively. The increase in cohesive intercept was not affected by the compaction water content, while the increase in friction angle was pronounced in specimens compacted at optimum water content (w = 18%). Durability tests showed that the improvement in strength due to hemp fibers diminishes after 3 weeks of curing prior to drained testing, indicating the dramatic negative impact of degradation of natural fibers on the mechanical performance of fiber-reinforced clay and the need for industrial treatment of the fiber.