Study on the effect of double mineral admixtures on the properties of high water materials

Abstract

In this paper, different contents of fly ash, silica fume, slag, and Nano-SiO2 were added to the high water material. Then, fly ash-silica fume, slag-silica fume, and Nano SiO2-silica fume are mixed into the high water material. Through the strength test of two groups of specimens, the influence of different types of mineral admixtures and blending ratios on the physical and mechanical properties of high-water materials was studied. The mechanical parameters of high water doped materials were measured by ultrasonic method, and the internal pore structure of high water doped materials was analyzed. In the case of double mixing, the optimal mixing amount is 4% fly ash and 6% silica fume, and the 7 d compressive strength of this group of specimens is increased by 15.85% compared with the original high water material. Through ultrasonic detection, the first wave is smooth and stable, the longitudinal wave amplitude curve is flat, the peak difference is slight, and the periodic amplitude is uniform, indicating that the structure of this group of specimens is dense. The shear modulus is increased by 20.31%, Young’s modulus is 1.3 times, and the volume modulus is 8.9 times that of the original high water material. The research findings suggest that high water materials can be modified by double mixing.