The resistance of high-strength concrete with ramie fiber using diatomaceous earth to high temperatures

Abstract

This study was conducted to evaluate the visual appearance, mass change, and compressive strength degradation of high-strength concrete (HSC) with the addition of 0%, 0.15%, 0.30%, and 0.45% ramie fiber. The diatomaceous earth was used to substitute the cement at a 10% replacement level. The HSC specimens were prepared and exposed to different temperatures which were 400 °C, 500 °C, and 600 °C. The exposure time was 5 h. After the exposure, an assessment of visual appearance, measurement of mass, and testing of compressive strength were conducted. Specimens exposed to a temperature of 400 °C only had a color change in visual appearance. At a temperature of 500 °C and 600 °C cracks on the specimen surface began to appear. Specimen mass loss increased with increasing temperature. Moreover, HSC exposed to high temperatures also experienced a decrease in compressive strength in which the compressive strength degradation increased with increasing temperatures. HSC with 10% diatomaceous earth as cement replacement had smaller compressive strength, but better resistance to high temperatures. Meanwhile, the presence of ramie fiber in an HSC mixture improved the compressive strength but lowered the resistance to high temperatures.