摘要
研制了一种液体中性喷射混凝土速凝剂。根据工程需要,试验研究了该速凝剂对不同品种水泥、不同减水剂以及预拌泵送混凝土的适应性。通过不同品种的水泥、不同减水剂的对比试验,测试评价速凝剂对水泥的凝结时间、强度等主要技术性能的影响。按工程特点,作了泵送剂掺入30min和60min后掺入液体中性速凝剂的凝结时间、不同龄期的强度试验;研究结果表明,新型的中性液体喷射混凝土速凝剂的各项指标符合JC477-1992《喷射混凝土用速凝剂》的技术要求,该速凝剂对于普通硅酸盐水泥适应性很好,1d抗压强度均大于8MPa,28d强度比均在90%以上,对于P.O42.5R水泥,28d抗压强度比均大于100%,尤其是盾石牌P.O42.5R水泥,28d抗压强度比达到127.8%。该速凝剂对普通硅酸盐水泥和高效减水剂具有很好的适用性,同时,与商品混凝土输送方式适应性也非常好,可以满足输送后喷射工艺的需要。
A liquid low-alkali setting-accelerator was prepared to use in shotcrete. The adaptability of setting-accelerator with various kinds of cement, different superplastieizer and premix pump delivered concrete were studied. By the contrasting experiment, setting time and strength of cement which compounding with different admixture were tested. According to the characteristic of engineering, mixing the pumping aid after 30min or 60min, the setting-accelerator was mixed in cement mortar, the setting time and strength of cement mortar were tested. The result shows that the initial setting time and the final setting time of cement paste achieve the standard requirement, and the compression strength of 1d is higher than 8MPa, the compression strength ratio of 28d is all larger than 90 %, To the P·O42.5R cement, the compression strength ratio of 28d is all larger than 100 %, especially Dunshi brand P·O42.5R cement is 127.8 %. The adaptability of setting-accelerator with normal Portland ce ment, superplasticizer and the transportation mode of ready-mixed concrete is satisfying.
出处
《混凝土》
CAS
CSCD
北大核心
2006年第1期48-50,62,共4页
Concrete
关键词
喷射混凝土
中性速凝剂
凝结时间
强度
shotcrete
neutral setting-accelerator
setting time
strength
