Abstract The early hydration of cementitious systems accelerated by an alkali-free aluminium sulphate based product was investigated in the presence and absence of fine limestone. The results show that the first seconds after the accelerator is added to the wet mix play a key role: Simultaneously to the massive ettringite formation, the Al2(SO4)3 accelerator favours the dissolution of the major cement clinker phase alite and thereby leads to an oversaturation of the pore solution with respect to calcium-aluminium-silicate-hydrates (C-A-S-H) and consequently the precipitation of nuclei of these phases. The surface of the limestone powder acts as an ideal substrate for these nuclei, which are the foundation for an outstanding early-strength-giving effect a few hours later.

中文翻译：

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硫酸铝加速胶凝体系的早期水化：细石灰石的影响

摘要 在存在和不存在细石灰石的情况下，研究了由无碱硫酸铝基产品加速的胶结体系的早期水化。结果表明，在湿混料中加入促进剂后的第一秒起关键作用：在形成块状钙矾石的同时，Al2(SO4)3 促进剂有利于主要水泥熟料相 alite 的溶解，从而导致相对于钙铝硅酸盐水合物 (CASH) 的孔隙溶液过饱和，从而导致这些相的晶核沉淀。石灰石粉末的表面是这些细胞核的理想基材，这些细胞核是几小时后产生出色早期强度效果的基础。