The test of fast-freezing method is employed to research the freezing resistance of C60 and C80 high-performance concrete with nanometer-SiO2, and XRD and SEM are employed to analyze the mechanism of its influence. Th...The test of fast-freezing method is employed to research the freezing resistance of C60 and C80 high-performance concrete with nanometer-SiO2, and XRD and SEM are employed to analyze the mechanism of its influence. The experimental results show that the freezing resistance of high-performance concrete has been effectively improved. The compressive strength of C60, C70 and C80 high-performance concrete added with nano-SiO2 can be improved by 8%, 6% and 5% respectively, the weight loss can be reduced by 1%, 0.6% and 0.3% respectively and the relative dynamic elastic modulus can be improved by 7%, 4% and 6% respectively after the 300 times freeze-thaw cycle.展开更多
文摘The test of fast-freezing method is employed to research the freezing resistance of C60 and C80 high-performance concrete with nanometer-SiO2, and XRD and SEM are employed to analyze the mechanism of its influence. The experimental results show that the freezing resistance of high-performance concrete has been effectively improved. The compressive strength of C60, C70 and C80 high-performance concrete added with nano-SiO2 can be improved by 8%, 6% and 5% respectively, the weight loss can be reduced by 1%, 0.6% and 0.3% respectively and the relative dynamic elastic modulus can be improved by 7%, 4% and 6% respectively after the 300 times freeze-thaw cycle.