The effect of fiber content on the static and dynamic performance of PE-ECC

Engineering cementitious composites (ECC) is an innovative high performance engineering structural material with high ductility, high toughness, and unique multiple cracking characteristics. Currently, most of the fibers used in ECC are expensive Kuraray PVA fibers produced in Japan. More and more researchers are using Polyethylene (PE) fibers made in China with low cost, high strength and high elastic modulus to replace Kuraray PVA fibers. However, the finer diameter and hydrophobicity make it difficult for the PE fibers to be distributed in the matrix evenly. In addition, most research currently focuses on the static performance of PE-ECC, with limited research on its dynamic performance. In this study, PE-ECC with different fiber contents was prepared with a high-power, high-speed mixer. Compressive tests, tensile tests and split Hopkinson pressure bar (SHPB) impact compression tests on the specimens were conducted to study their static and dynamic performance. The results indicated that increasing the fiber content can improve the mechanical properties of PE-ECC when the fiber volume fraction is low. Further increasing the volume fraction of fibers will affect the uniform distribution of fibers, leading to a decrease in the mechanical properties of PE-ECC and an increase in the discreteness of test results. Considering the difficulty of fiber dispersion and mechanical properties, it is recommended that the content of PE fiber should not exceed 2.25%. The research results of this paper may provide a reference for the promotion and application of PE-ECC, especially in the field of collision protection.