助磨剂对水泥与减水剂相容性的影响及改善

以净浆流动度作为水泥与减水剂相容性的评价指标,试验研究了多种助磨剂对水泥与萘系减水剂或聚羧酸减水剂相容性的影响规律,探讨了缓凝剂和引气剂对水泥与减水剂相容性的改善作用。结果表明,助磨剂对水泥与萘系减水剂相容性的影响较大,对水泥与聚羧酸减水剂相容性的影响较小。缓凝剂和引气剂均能改善水泥与萘系减水剂的相容性,随其掺加量的增加,改善作用逐渐增大。含缓凝剂/引气剂的复合助磨剂对水泥净浆流动度有一定的改善作用,并延缓水泥的凝结时间。含缓凝剂的复合助磨剂对水泥有增强作用,而含引气剂的复合助磨剂会降低水泥的胶砂强度。

Effect of Grinding Aids on the Compatibility of Cement and Water Reducer and Its Improvement Methods

Effect of multiple frequently used grinding aids on the compatibility of cement and water reducer is evaluated by cement paste fluidity, and improvement of retarder and air-entraining agent on compatibility of cement and water reducer is discussed. The results show that the effect of grinding aids on the compatibility of cement and naphthalene superplasticizer is large, while its effect on the compatibility of cement and polycarboxylate superplasticizer. Both the retarder and air-entraining agent can improve the compatibility of cement and naphthalene superplasticizer, and the improvement is gradually significant with the increase of the dosage of retarder or air-entraining agent. The fluidity of cement paste is improved by composite grinding aids containing retarder or air-entraining agent, and the setting time of cement is delayed. The strength of cement mortar is improved by the composite grinding aids containing retarder, while the strength is reduced by the composite grinding aids containing air-entraining agent.