混杂纤维对C60 HPC高温性能的影响

Effects of hybrid fiber on properties of C60 high performance concrete exposed to high temperature

为了研究混杂纤维对C60高性能混凝土(简称"HPC")高温性能的影响,对掺混杂纤维的C60 HPC进行模拟火灾试验,利用红外热像仪检测HPC试件红外热像平均温升,并分别测试HPC试件抗压强度和劈拉强度,分析HPC抗压强度、劈拉强度、平均温升与受火温度的关系。结果表明,随受火温度提高,PS11和PS21试件红外热像平均温升均呈上升趋势;PS11和PS21试件的抗压强度总体呈下降趋势,但均在400℃出现反弹。分析认为,200~400℃时,聚丙烯纤维熔化所形成的孔道,缓解了混凝土内部的蒸汽压,一定程度上提高了HPC的高温性能;钢纤维可以显著改善HPC高温力学性能。

To study the influence of hybrid fibers on the performance of high temperature of C60 high performance concrete(HPC),simulated fire test was performed on C60 HPC reinforced with the hybrid fibers.Using the infrared thermal imaging technology,the infrared average temperature rising of high performance concrete was tested.The compressive strength and splitting tensile strength of high performance concrete were tested.The relationship between the fire temperature and infrared average temperature rising,the compressive strength,splitting tensile strength were analyzed.Results showed that as the increase of the fire temperature,infrared average temperature rising of PS11 and PS21 was on the rise;the compressive strength and the tensile strength of the specimens is on the decline in general,but the compressive strength of PS11 and PS21 rebounded at 400℃.It was believed that the holes formed by the melting of polypropylene fiber alleviated the vapor pressure inside the concrete and improved the performance of high temperature of HPC to a certain extent during 200~400℃;and the steel fiber can improve the mechanical properties of high temperature of HPC significantly.