(1. 江西理工大學 資源與環(huán)境工程學院，贛州 341000；
2. 江西理工大學 江西省礦業(yè)工程重點實驗室，贛州 341000)
摘 要: 針對超細全尾砂-水泥膠結(jié)膏體充填料漿黏性大、和易性差，其滿足充填輸送要求時充填體強度低的問題，通過不同摻量聚羧酸高效減水劑對膏體料漿流動度、坍落、泌水率及其充填體抗壓強度影響的試驗研究，并借助XRD能譜分析和電鏡掃描(SEM)方法，從微觀角度揭示減水劑提到充填體強度機理。結(jié)果表明：摻量0.5%(質(zhì)量分數(shù))的聚羧酸高效減水劑可使質(zhì)量分數(shù)為70%~76%膏體充填料漿的流動度、坍落度有效增加；料漿泌水率明顯提高，但不會發(fā)生嚴重離析；充填體微觀上水泥水化凝膠更多，尾砂顆粒因水化凝膠“包裹”作用形成更大的晶體顆粒，且顆粒分布更為均勻、孔隙更小、結(jié)構(gòu)更為致密，宏觀上初期/長期強度顯著提高，最高達50%;同時，減水劑摻量小于0.5%為“安全摻量”，對充填體強度不會造成劣化影響。
關鍵字: 聚羧酸減水劑；膏體充填；超細全尾砂；流動性；充填體強度；微觀機制
（1. School of Resource and Environmental Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China;
2. Jiangxi Key Laboratory of Mining Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:Considering the problem of the super fine tailings cemented paste backfill slurry high viscosity, poor workability, and the filling body with low strength while the slurry satisfies the requirements of pipelines transportation, the effects about different dosages Polycarboxylate-based superplasticizer on fluidity, slump, bleeding of paste slurry and its compress strength of filling body were studied. From the microscopic point of view, the mechanism of superplasticizer was revealed to improve the strength of the filling body by the means of XRD and SEM. The results show that, firstly, when the dosage is 0.5%, the paste slurry fluidity and slump of the mass fraction from 70% to 76% are effectively increased. Secondly, although slurry bleeding rate is significantly improved, it could not severely segregated. Thirdly, from the micro level, the backfill body has more cement hydration products; tailings particles become larger crystal particles due to “package” by hydration products, which is distributed more uniformly, has smaller porosity and more compact micro structure. All in all, from the macro level, early or long-term strength significantly increases to 50% at most. Meanwhile, the dosage below 0.5% is “safe adding amount”, which would not cause a bad influence on filling body strength.
Key words: polycarboxylate-based superplasticizer; paste backfill; super fine tailing; fluidity; filling body strength; microscopic mechanism
