Effect of Nano-CaCO₃ on Compressive Strength Development of High Volume Fly Ash Mortars and Concretes

摘要

This paper presents the experimental results on the effect of nano-CaCO_(3) on compressive strength development of mor-tars and concretes containing high volume fly ash (HVFA). The effect of various nano-CaCO_(3) contents such as 1, 2, 3 and 4% (wt.%) as partial replacement of cement on the compressive strength of mortars are evaluated in the first part. The nano-CaCO_(3) content which exhibited the highest compressive strength above is used in high volume fly ash mor-tars and concretes containing 40% and 60% class F fly ash. The results show that among four different nano-CaCO_(3) contents, the addition of 1% nano-CaCO_(3) increased the compressive strength of mortars and concretes. The addition of 1% nano-CaCO_(3) also increases the early age and 28 days compressive strengths of HVFA mortars and concretes. The X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analysis results also support the above findings.