(1. 江西理工大学 资源与环境工程学院，赣州 341000；
2. 江西理工大学 江西省矿业工程重点实验室，赣州 341000)
摘 要: 针对超细全尾砂-水泥胶结膏体充填料浆黏性大、和易性差，其满足充填输送要求时充填体强度低的问题，通过不同掺量聚羧酸高效减水剂对膏体料浆流动度、坍落、泌水率及其充填体抗压强度影响的试验研究，并借助XRD能谱分析和电镜扫描(SEM)方法，从微观角度揭示减水剂提到充填体强度机理。结果表明：掺量0.5%(质量分数)的聚羧酸高效减水剂可使质量分数为70%~76%膏体充填料浆的流动度、坍落度有效增加；料浆泌水率明显提高，但不会发生严重离析；充填体微观上水泥水化凝胶更多，尾砂颗粒因水化凝胶“包裹”作用形成更大的晶体颗粒，且颗粒分布更为均匀、孔隙更小、结构更为致密，宏观上初期/长期强度显著提高，最高达50%;同时，减水剂掺量小于0.5%为“安全掺量”，对充填体强度不会造成劣化影响。
关键字: 聚羧酸减水剂；膏体充填；超细全尾砂；流动性；充填体强度；微观机制
（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
