Effect of temperature on the tensile properties of fabric-reinforced cementitious matrix composites

Fabric-reinforced cementitious matrix (FRCM) composites are less susceptible to high temperatures than traditional fiber-reinforced polymer (FRP) structures. However, the tensile properties of FRCM composites after hightemperature exposure are still an open issue. In this paper, the residual tensile properties of FRCM samples which comprise basalt textile reinforcement embedded in the engineered cementitious composites (ECC) exposed to elevated temperatures of 20 degrees C, 200 degrees C, 400 degrees C, and 600 degrees C were investigated through direct tensile tests. The effect of basalt textiles was also examined using the textile reinforcement ratio of 0, 0.44 %, 0.88 %, and 1.32 % at all four reinforcement levels considered. High-temperature resistances of the FRCM were then quantified in terms of the stress-strain curve, tensile strength, deflection, stiffness, and mass loss. The experimental results indicated that FRCM exhibited multiple-crack patterns similar to ECC when the temperature was below the melting point of polyvinyl alcohol (PVA) fibers (i.e., 230 degrees C). At 20 degrees C and 200 degrees C, increasing the textile reinforcement ratio can significantly improve the tensile strength. However, at 400 degrees C and 600 degrees C, there was a significant decrease in ultimate strength and cracked elastic modulus, dropping to 60-70 % of their initial values. In this case, the increase in textile reinforcement ratio did not affect the results, as the bond between the basalt fibers and the ECC matrix was poor. The microstructure of samples was examined using scanning electron microscopy (SEM), which provided a clear insight into the macroscopic behavior changes in the FRCM samples. A stress-strain model considering the temperature effect was proposed for FRCM. The model predictions showed a good correlation with the experimental results.