Influence of natural fibers on physical, mechanical, and fire‐resistant properties of microconcrete

This study examined the influence of natural fibers on the physical, mechanical, and fire‐resistant properties of microconcrete, in comparison with conventional polypropylene fibers used in cement composites. The fibers were characterized by FTIR and TGA/DSC to assess their composition and thermal stability, and FTIR was also performed after thermal testing to evaluate structural changes. A reference microconcrete and six fiber‐reinforced mixtures with varying fiber types and dosages were prepared. Workability was evaluated in the fresh state, while tests on hardened specimens included water absorption and toughness, as well as the compressive strength, flexural strength, and the mass of the specimens, all three of which were measured before and after exposure to 400°C. To interpret the results, the microstructure of selected specimens was analyzed using SEM. The incorporation of natural fibers enhanced post‐cracking behavior and toughness while maintaining comparable compressive strength to the reference mixture. Fire tests demonstrated improved resistance to microcracking, confirming the potential of natural fibers to improve the toughness and fire performance of microconcrete.