Abstract: Microsilica is able to improve the strength and durability of concrete, but the effect of microsilica on adiabatic temperature rise of concrete is unclear. Researchers had even obtained contradictory findings. In this study, 15 concrete samples mixed with microsilica of varied content at different water-binder ratios were produced for semi-adiabatic temperature rise experimental measurement, and then the adiabatic temperature rise of each concrete sample was calculated with the heat loss compensation technique. Results demonstrated that the addition of microsilica could suppress the adiabatic temperature rise at the same water-binder ratio and the same strength. The adiabatic temperature rise amounted to 1.8~7.3 ℃ in the presence of 5% microsilica, and 3.3~10.2 ℃ in the presence of 10% microsilica. The suppression of adiabatic temperature rise was affected by water-binder ratio. On the basis of the result of adiabatic temperature rise, the predication formula and design chart for predicting adiabatic temperature rise of microsilica concrete were presented.

Key words: mass concrete, microsilica, adiabatic temperature rise, heat loss compensation, water-binder ratio