(1. 北京科技大学 土木与资源工程学院，北京 100083；
2. 金属矿山高效开采与安全教育部重点实验室，北京 100083)
摘 要: 以谦比希铜矿的尾砂作为试验样品，对质量分数为64%~73%的尾砂浆体进行流变试验，研究其流变特性，预测该矿膏体的临界浓度。传统测量方法认为流动性指数为1时的料浆浓度即为临界浓度，试验发现，该方案得到的数值较为保守。研究料浆浓度与其屈服应力之间的关系，发现两者呈显著的DoseResp函数关系，为精确预测料浆特性提供有效方法。得到屈服应力随料浆浓度变化的演化规律，基于屈服应力增长速率，演化分为两个阶段：单调递增阶段和单调递减阶段。屈服应力在浓度变化范围内具有极大值和极小值，可以通过DoseResp函数精确预测，而屈服应力变化速率的“极大值点”即为“临界浓度”。因此，确定谦比希铜矿膏体临界浓度为70.73%，与试验结果吻合。
关键字: 尾砂；流变学；临界浓度；屈服应力；演化规律
（1. School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, Beijing 100083, China）
Abstract:The rheological experiments on slurries with mass fraction of 64% to 73% were implemented using tailings from Chambishi Copper Mine to study the rheology and determine critical concentration of paste tailings. Previous studies thought the critical concentration was determined when value n is 1. However, recent experiments show that method underestimates critical concentration of paste tailings. The relationship between slurry concentration and yield stress through investigation, which accurately predicts slurry characteristics, is found with function DoseResp fitting. The evolution law of yield stress in paste tailings consists of two stages. The growth rate of yield stress increases in former stage but decreases in the later. Besides, maximum and minimum yield stress exist. The critical concentration is confirmed as maximum growth rate of yield stress emerges. Hence, the critical concentration of paste tailings from Chambishi Copper Mine is 70.73%, which coincides with experiment results.
Key words: tailings; rheology; critical concentration; yield stress; evolution law
