掺聚丙烯纤维高性能混凝土高温后的抗压性能

Study on Compressive Behavior of HPC with PP Fiber at Elevated Temperature

设计了79块掺有聚丙烯纤维的C50,C80和C100高性能混凝土立方体试块,在经历了20～900℃的温度后,得出了外掺聚丙烯纤维高性能混凝土高温后的质量损失率和残余抗压强度,以及未发现高温爆裂的结论.分别针对试块尺寸、强度等级和经历温度等因素,研究了聚丙烯纤维高性能混凝土的高温抗压性能,通过统计回归分析,得出了可供工程设计和事故鉴定用的抗高温设计曲线.

79 cube specimens were designed and fabricated with C50, C80 and C100 high performance concrete (HPC) reinforced with polypropylene(PP) fiber. After these cube specimens were heated in an electric stove, with series temperature ranging from 20 to 900 ℃, respectively, the relationship between the mass loss and exposure temperature was investigated. Then the heated and cooled specimens were tested under monotonous compressive loading, the degradation of the residual compressive strength was studied. Concerning the effects of the cube dimension, strength grade and different elevated temperatures, the compressive behavior of HPC with PP fiber is comparatively discussed. Finally, a fire-resistance design curve between residual compressive strength and exposure temperature is established according to the statistic analysis of test data.