Effect of Heat and Impact on Self-Compacting Concrete Containing Polypropylene Fibers

Many primary behavioral properties of concrete, including flexural strength, fatigue resistance, impact, thermal shock and brittle fracture could be improved by using reinforcing fibers into the concrete. The present study deals with the physical and mechanical behavior of Self-Compacting Concrete (SCC) containing polypropylene fibers as well as the effect of polypropylene fibers on increasing the strength of SCC and increasing its impact resistance and thermal properties. To this aim, self-compacting concrete containing 0, 0.1 and 0.3 percent by volume of polypropylene fibers was used. In order to investigate the effect of heat on the fiber-reinforced concrete, experiments were carried out on the specimens with 28 days of age, which were exposed to 250 degrees C temperature for 8 hours. In this research, 6 cylindrical compressive test specimens, 6 tensile test specimens and 15 rectangular beams are built. Results showed that tensile strength and impact resistance are improved by increasing the presence of fibers in SCC. It was found that by adding fibers, impact resistance has increased up to 140%. Concerning the effect of fibers on the heated concrete containing fibers, it was found that fibers reduce the negative effect of heat on compressive strength, tensile strength as well as on impact resistance.