【摘要】 研究了单掺高价阳离子硫酸盐对混凝土早期强度的影响 ,结果显示其对水泥、混凝土具有促凝作用 ,使混凝土早期强度降低。正交试验得出高价阳离子硫酸盐掺量为 0 .5 %、缓凝组分羟基羧酸为 0 .0 15 %时 ,混凝土的早期 1d、3d强度分别提高 32 %和 17% ,而后期 2 8d强度无降低。机理分析表明 ,单掺高价阳离子硫酸盐能使水泥在水化初期迅速生成大量钙矾石而导致速凝 ,但恰当复合缓凝组分后既能使钙矾石难以过快生成避免速凝 ,从而发挥其有利方面的作用 ;又能因其含有硫酸根和高价离子 ,前者可生成较多的 AFt,后者聚沉作用强 ,加快硅酸盐矿物的水化 ,生成更多的C- S- H,使结构更加密实 ,提高了混凝土强度更多还原

【Abstract】 The influence of the high valence cation sulfate on early strengh of concrete was studied. The results showed that the concrete flash set and the early strength of concrete is reduced when the high valence cation sulfate is added. However by orthogonal design experiments the early concrete strength of 1 d and 3 d increased 32% and 17% when the high valence cation sulfate content was 0.5% and the hydroxycarboxylic was 0.015%. The strength at 28 d is not reduction. The study of mechanism indicated that the flash setting of concrete is due to ettringite produce rapidly at the beginning of hydration. When the high valence cation sulfate is mixed with hydroxycarboxylic in a properly proportion, a large number AFt and C-S-H are formed, the structure of concrete became dense and thus the strength is improved.更多还原