水下不分散混凝土拌合物工作性控制技术

Study on Techniques for Controlling Workability of Non-dispersible Underwater Concrete Mixture

采用对比性试验方法,综合分析了原材料各组分间的相容性关系以及掺合料品种与数量、搅拌时间、细骨料细度模数的影响,并测定了运输车的辅助搅拌功能.结果表明,采用水下不分散砂浆的原材料相容性试验可简化试验过程,快速判定合适的减水剂品种;活性矿物掺合料的掺量直接影响混凝土拌合物的坍扩度;合适的搅拌时间可以最大程度地发挥絮凝剂和减水剂的功能;采用中砂偏粗的品种有利于施工过程的正常运转;运输车的辅助搅拌功能可改变混凝土混合料的絮凝聚集结构.

A series of contrast tests were carried out. The compatibility of the original materials, the influence of varieties and quantities of active mineral admixtures, mixing time, the modulus of fine aggregate on the degree of slump-flowability property (S-F) of concrete mixture were analysed. The auxiliary churning function in transportation was determined. The results show that the compatibility of the raw materials can be simplified by non-dispersible underwater cement mortar, the added amount of active mineral admixture will directly exert an influence on S-F of concrete mixture, the middle sand with higher fineness modulus will be in favour of site-mixed concrete, and the auxiliary churnning function in transportation can fully change the flocculation configuration in concrete mixture.