消防射水与自然冷却下玻璃纤维对灾后混凝土性能影响

本文对火灾后消防射水对玻璃纤维改性混凝土(GF-1)剩余抗压强度的影响进行了研究。分析了GF-1在不同温度、不同冷却方式条件下抗压强度的变化规律,并利用ORIGIN7.5软件拟合了高温作用后GF-1剩余抗压强度与温度之间的关系。研究得出:在两种冷却条件下,二种配比的HPC在高温后剩余抗压强度均呈持续降低,消防射水冷却条件下HPC的剩余抗压强度降低速率大;加热到900℃时,消防射水冷却条件下HPC的剩余抗压强度最低;消防射水对高温作用后GF-1的剩余强度影响很大,射水冷却后GF-1剩余强度明显低于自然冷却的剩余强度;且随着破坏温度升高,经消防射水冷却的GF-1剩余抗压强度呈衰减状态,;GF-1在射水冷却下强度变化没有NC-1快速,与自然冷却条件下的强度变化相比,也呈现出不同的衰减规律;并建立了自然冷却条件下及消防射水冷却条件下GF-1剩余强度与火场温度之间的多阶多项式拟合式。

Study on residual compressive strength of high-performance concrete influenced by fire spraying and room temperature after fire

This paper discussed the residual compressive strength of high-performance concrete （GF-1） influenced by fire spraying after fire.The variation of compressive strength of GF-1 at different temperature and different cooling method was analyzed.The relationship of residual compressive strength with tolerable temperature of GF-1 was drafted by ORIGIN 7.5 software.The results showed the residual compressive strengths of two kind of HPC were continuously reduced without exception,and furthermore the method of fire spraying would accelerate the decline of the residual compressive strength of samples.When the temperature reached at 900℃,the residual compressive strength of HPC samples cooled by fire spraying was less.The residual compressive strength of GF-1 under the condition of high temperature could be remarkably decreased by fire spraying.And the residual compressive strength of GF-1 cooled by fire spraying would continuously be decreased with increasing of the damaged temperature of the samples.On the other hand,the change of intensity of NC-1 sample was bigger than GF-1 sample under the condition of fire spraying,and the decrease disciplinarian of intensity under fire spraying was clearly different with that of intensity under room temperature.Moreover,it was founded that the polynomial fits represented the relationship of residual compressive strength of GF-1 cooled by fire spraying and room temperature with fire temperature.