Tensile characteristics of carbon textile-reinforced mortar incorporating short amorphous metallic and nylon fibers under designed environmental conditions

Abstract

This study experimentally investigated the mechanical tensile properties of carbon textile-reinforced mortar (TRM) composites utilizing amorphous metallic and nylon short fibers with lengths of 15 and 12 mm, respectively, at 0.4 % and 0.7 % fiber content under the designed conditions. The conditions of the ambient control, water immersion, sulfate immersion, and wet-dry cycle sulfate attack were designed to investigate the tensile characteristics of the TRM composite and the effectiveness of applying short fibers under normal and harsh environments accelerated using a temperature and humidity machine. The experiments included tensile tests for dried carbon textiles, water absorption tests for mortar matrices with and without short fibers, external damage inspection for TRM specimens and compressive tests for mortar matrices after exposure to the designed conditions. Furthermore, based on RILEM TC 232-TDT, tensile tests of 60 TRM specimens were performed after exposure to the designed conditions. The results indicate that the existence of both amorphous metallic and nylon short fibers significantly improves the TRM tensile properties under all conditions, in which the amorphous metallic fiber was found to be more effective at low strain levels, whereas the positive effect generated by nylon fibers only considerably appeared at high strain values. In addition, a positive effect was observed under the prolonged water immersion condition. Besides, the TRM specimens without short fibers were severely damaged under the designed sulfate attack, and utilizing them could prevent the propagation of the damage, in which applying 0.4 % nylon fibers proved to provide the highest resistance capability.