Enhancing the properties of concrete using C-S-H seed has been a challenging task due to its agglomeration in the cement matrix. Here, for ensuring synthetic C-S-H disperse well in the cement matrix, it was first synthesized in situ on fly ash (FA) by co-precipitation method, and the C-S-H grown in situ on FA (C-S-H@FA) was received. And then, its phase composition, morphology and particle size distribution were studied. After that, its effect on the hydration kinetics of cement, and the workability, strength development, pore structure, durability of concrete was explored. The results showed that the hydration of cement can be stimulated more dramatically by C-S-H@FA when compared with C-S-H, as well as the strength development of concrete. Besides, the addition of C-S-H@FA can refine the pores in concrete, and make concrete more compact than incorporating C-S-H. Furthermore, when C-S-H was replaced by C-S-H@FA, the carbonation resistance and drying shrinkage resistance of concrete was improved. Therefore, it can be concluded that the C-S-H grown in situ on FA has better dispersibility than C-S-H in concrete, improving the comprehensive properties of concrete more effectively.

由于CSH种子在水泥基体中的团聚，使用CSH种子增强混凝土的性能一直是一项艰巨的任务。在这里，为了确保合成的CSH在水泥基体中的分散良好，首先通过共沉淀法在粉煤灰（FA）上原位合成了CSH，然后接收了在FA（CSH @ FA）上原位生长的CSH。然后，研究了其相组成，形态和粒度分布。之后，探讨了其对水泥水化动力学的影响，以及对混凝土的可加工性，强度发展，孔结构和耐久性的影响。结果表明，与CSH相比，CSH @ FA可以更显着地促进水泥的水合作用，并增强混凝土的强度。此外，添加CSH @ FA可以细化混凝土中的孔，并使其比掺入CSH的混凝土更致密。此外，当用CSH @ FA代替CSH时，混凝土的抗碳化性和抗干缩性得到改善。因此，可以得出结论，在FA上原位生长的CSH比CSH在混凝土中具有更好的分散性，从而更有效地改善了混凝土的综合性能。