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

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% and 10% SF at 600 °C were 6.7% and 14.1% 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 °C, whereas the amount of SF had considerable influences on the residual compressive strength above 300 °C similar to the response at 600 °C. The optimum dosage of SF and w/c was found to be 6% and 0.35, respectively.