An exploratory study on high-volume fly ash concrete incorporating silica fume subjected to thermal loads

作者：Rashad Alaa M^*

来源：Journal of Cleaner Production, 2015, 87: 735-744.

DOI：10.1016/j.jclepro.2014.09.018

• EIVFA
• Silica fume
• Relative strength
• Residual compressive strength
• Elevated temperature

In this study, cement has been partially replaced with a Class F fly ash (FA) at a level of 70% to produce high-volume fly ash (HVFA) concrete (F70). F70 was modified by partially replacing FA with silica fume (SF) at levels of 10% and 20%, by weight. All HVFA concrete types were compared to the neat Portland cement (PC) concrete. After curing, the specimens were exposed to elevated temperatures ranging from 400 degrees C to 1000 degrees C with an interval of 200 degrees C. Weight and compressive strength before and after firing have been thoroughly explored. The various decomposition phases formed were identified using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicated higher relative strength of all HVFA concrete types. F70 exhibited the highest relative strength. The SF blends exhibited good fire performance up to 600 degrees C, then severe degradation in the residual strength was observed at 800 and 1000 degrees C.

• 出版日期2015-1-15