Effects of silica fume addition and water to cement ratio on the properties of high-strength concrete after exposure to high temperatures

摘要

This paper presents the results of an experimental investigation on the effect of different amounts of silica fume (SF) and water to cement ratios (w/c) on the residual compressive strength of high-strength concrete after exposure to high temperatures. Based on the results obtained the rates of strength loss for concrete specimens containing 6 percent and 10 percent SF at 600 deg C were 6.7 percent and 14.1 percent lower than those of the ordinary concrete. The dosage of SF had no significant effect on the relative residual compressive strength at 100 and 200 deg C, whereas the amount of SF had considerable influences on the residual compressive strength above 300 deg C similar to the response at 600 deg C. The optimum dosage of SF and w/c was found to be 6 percent and 0.35, respectively.