超缓凝混凝土是一种凝结时间较长、早期强度较低、后期强度发展较快的新型混凝土。本文探讨了水灰比、砂率、矿物掺合料掺量对超缓凝混凝土性能的影响，以水灰比、砂率、矿物掺合料掺量为单一变量，利用聚羧酸和蔗糖为减水剂和缓凝剂，分别测定了混凝土流动性能、凝结性能及抗压强度。结果表明，超缓凝混凝土的砂率宜选择35%~45%；水灰比在0.30~0.80范围，混凝土28d抗压强度随水灰比增加而降低，凝结时间随水灰比增加而增加；粉煤灰和矿粉的掺入可以改善超缓凝混凝土的工作性能，超缓凝混凝土后期强度随粉煤灰或矿粉取代量增加而降低。%Super-retarding concrete is a new concrete, which has longer setting time, lower early strength, later strength rapid development. The effects of water-cement ratio, sand ratio, mineral admixture content on the property of the super-retarding concrete are discussed in this paper, using water-cement ratio, sand ratio, mineral admixture content as the single variable, using polycarboxylic acid and sucrose as the water reducer and setting retarder, the flow properties, coagulation properties and compressive strength of concrete are determined. The results show that sand ratio of super-re-tarding concrete should be 35%~45%, water-cement ratio in the range of 0.3~0.8, 28d compressive strength of the con-crete decrease with water-cement ratio increasing, the setting time increase with water-cement ratio increasing, fly ash and slag can improve the workability of super-retarding concrete, the later strength of super-retarding concrete decrease with the substituted amount of fly ash or slag increasing.
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