Effects of elevated temperature attack on nano-Al2O3 particles blended Ultra High Performance Concrete

In the present investigation, the thermal resistance behavior of ultra high performance concrete (UHPC) containing nano Al2O3 particles has been investigated at the age of 56th day. A partially cement was partially replaced by 0.5%, 1%, 1.5%, 2% and 3% nano Al2O3 particles. The change in weight and change in compressive strength of the produced specimens were measured, after 4 hours exposed in elevated temperature about 300°C, 600°C and 900°C at a rate of heating 10°C/min. After the 4-hours of soaking period, the exposed samples were examined at both micro and macro scales to explore the colour transformations, change in weight, change in strength, cracking and spalling behavior of UHPC at 300°C, 600°C and 900°C. The 2% of nano Al2O3 particles improved spalling resistance compared with all other mix proportions. The obtained result reveals that, 2% of nano Al2O3 particles efficiently used in UHPC performed better in elevated temperature.