水泥中石膏对萘系减水剂作用效果的影响研究

Study on the influence of gypsum in cement on naphthalene type water-reducer

混凝土外加剂与水泥相容性问题的影响因素很多,其中石膏的种类和掺量就是其中之一。以减水剂为例,其在水泥混凝土应用中存在饱和点,通过饱和点的变化可判定水泥与减水剂的相容性好坏。采用不同石膏掺量,不同高效减水剂掺量的水泥净浆试验,进行5,30,60min的净浆流动度的测试及饱和点的确定。结果表明,随着水泥中石膏含量的增加,减水剂的饱和点不断降低,饱和点时净浆流动度不断下降,水泥与减水剂的相容性越差。另外,还对石膏品种对减水剂相容性的影响进行了概要性的介绍。

There are many factors related to the adaptability between concrete addition agent and cement, and the type and adding rate of gypsum is one of them. For water reducer, there has a saturation point in the concrete application, and which decided the adaptability between cement and water reducer. Fluidity and the saturation point at 5,30,60 min of the motar which had different gypusm and water recucer adding rate were tested. The results show that with the adding of gypsum, saturation point of the water reducer decreased, and as well as the fluidity which indicated a worse adaptability. Finally, the influence of gypsum type were introduced synoptically.