The resistance to chloride penetration of concrete containing nano-particles (TiO2 and SiO2) for pavement is experimentally investigated and compared with that of plain concrete, the concrete containing polypropylene (PP) fibers and the concrete containing both nano-particles and PP fibers. The test results indicate that the addition of nano-particles (TiO2 and SiO2) improves the resistance to chloride penetration of concrete. The effectiveness of nano-TiO2 in improving the resistance to chloride penetration reduces with increasing content of nano-TiO2, and the similar results can be found for the concrete containing nano-SiO2. The resistance to chloride penetration of concrete containing nano-TiO2 is better than that containing the same amount of nano-SiO2. However, the resistance to chloride penetration of concrete containing PP fibers is decreased. The larger the content of PP fibers is, the lower the resistance to chloride penetration of concrete is. For the concrete containing both nano-particles and PP fibers, the resistance to chloride penetration is also reduced and even lower than the concrete only containing the same amount of PP fibers. The relationship between the chloride diffusion coefficient and compressive strength of concrete approaches hyperbola basically, which shows that the resistance to chloride penetration of concrete enhances with increasing compressive strength and proves that compressive strength is an important factor influencing the resistance to chloride penetration of concrete.
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