基于最紧密堆积理论超密实再生砂浆制备研究

再生混凝土或再生砂浆通常被认为力学和耐久性能较低，为研究再生水泥基材料性能，利用颗粒最紧密堆积理论，根据超细再生微粉和超细矿物掺合料颗粒粒径分布，将不同细度颗粒进行合理掺配，使胶凝体系最大程度上接近紧密堆积，制备出超密实再生砂浆，并计算粒径分布的分形维数，探讨其对抗压强度和孔隙率的影响。研究结果表明：最紧密堆积的混合料粒径分布具备分形特征，粒径分布的分形维数值越小，颗粒粒径分布越复杂，整体密实程度越高；粒径分布分形维数值较高的混合胶凝粉体，制备的试样早期强度较低。此外，利用最紧密堆积原理制备的超密实胶凝体系的孔隙率低于简单混合的胶凝体系试验组的孔隙率，孔径分布也更合理。

Research on super dense recycled mortar preparation based on densified parking theory

It's known that both the mechanism and durability of recycled concrete and mortar are considerably lower than normal concrete. To study the influences of superfine mineral admixture on recycled mortar, super dense recycled mortar was made by mixing the recycled powder and mineral admixtures in certain proportion to make the particle size distribution similar to that of the dense parking state according to the densified parking theory. And subsequently, fractal dimension of particle size distribution was determined to characterize the compressive strength and porosity. The experimental results show that the fractal dimension can characterize the particle size distribution of mineral admixtures, the smaller fractal dimension value, the higher degree of compactness, the more complicated the particle size distribution. Furthermore, specimens with higher particle size distribution fractal dimension have lower strength at early stage. In addition, super dense cementitious material prepared by DSP theory has lower porosity than that made by simply mixing of fine mineral admixtures, and its pore size distribution is relatively more reasonable.