磷渣硅酸盐水泥的缓凝产物及改性研究

为确定磷渣硅酸盐水泥的缓凝产物,将硅酸盐熟料粉末与磷渣各自在去离子水中浸泡5h并过滤,再将溶液混合后静置12h获得羟基磷灰石Ca5(PO4)3OH沉淀,由于羟基磷灰石的生成覆盖在水泥颗粒表面,阻碍了水化反应,从而导致磷渣硅酸盐水泥的缓凝；另外,通过掺加5％的硫铝酸盐水泥,能较大程度缓解磷渣硅酸盐水泥的缓凝特征,同时还能提高水泥3d和28d抗压强度.

Retarding product of Phosphorous slag cement and its modification

In order to ascertain the retarding product of phosphorous slag cement, Portland clinker powder and phosphorous slag were soaked in deionized water for 5 hours and then filtrated respectively, hydroxyapatite precipitation （Ca5（PO4）3OH） was obtained by mixing the two solutions together and standing for 12 hours. The generation of hydroxyapatite would cover the surface of cement particles and then hinder the hydration reaction, which was the cause of the retardation of phosphorous slag cement. In addition, the retarding characteristic of phosphorous slag cement could be ameliorated in some extent by adding 5% sulfuraluminate cement, and the compressive strength of 3d and 28d of phosphorous slag cement could also be improved.