This paper presents results of an experimental study on the compressive and splitting tensile strength of plain concretes and concretes incorporated with macro, micro and hybrid polypropylene (PP) fibers at elevated temperatures (20 °C, 200 °C, 400 °C, 600 °C, and 800 °C). Nine series of concrete mixtures with different contents PP fibers were prepared and the optimum mixing proportion of different sizes of PP fibers was discussed. The results indicated that the multi-scale polypropylene fiber reinforced concrete (dropped with three different sizes of PP fibers into concrete) had the best positive hybrid effect on resisting to high temperature, when the total PP fiber content was 6 kg/m³ and the macro PP fiber substitution was 80%. Meanwhile, the addition of macro PP fibers significantly enhanced the toughness of concrete. Compared with the value of plain concrete, the compressive and splitting tensile strength of the optimal multi-scale polypropylene fiber reinforced concrete at 800 °C increased 14% and 36% respectively.

本文介绍了在高温（20°C，200°C，400°C，600°C）下对普通混凝土以及掺有宏观，微观和混杂聚丙烯（PP）纤维的混凝土的抗压强度和劈裂抗张强度的实验研究结果。 C和800°C）。制备了9种不同含量PP纤维的混凝土混合料，讨论了不同尺寸PP纤维的最佳配合比。结果表明，当聚丙烯纤维的总含量为6 kg / m ³时，多尺度聚丙烯纤维增强混凝土（将三种不同尺寸的PP纤维滴入混凝土中）具有最佳的耐高温混合效果。大型PP纤维替代率为80％。同时，添加大PP纤维可显着提高混凝土的韧性。与普通混凝土相比，最佳多尺度聚丙烯纤维增强混凝土在800°C时的抗压强度和劈裂抗拉强度分别提高了14％和36％。