(1. 北京科技大学 土木与资源工程学院，北京 100083；
2. 北京科技大学 金属矿山高效开采与安全教育部重点实验室，北京 100083)
摘 要: 全尾砂充填膏体具有多尺度、高浓度颗粒悬浮液的特征，传统黏塑性流变模型是否适应于膏体的流变行为是需要研究的重要问题。本文从传统H-B流体对全尾砂膏体的适应性研究入手，首先建立H-B流体的适应性约束条件，选择适宜多尺度、高浓度膏体的流变测量系统与数据转换方法，采用控制剪切速率(CSR)、控制剪切应力(CSS)两种流变测量模式，开展全尾砂膏体流动曲线测量实验。结果表明：流动曲线在CSR测量模式下具有负斜率现象、CSS测量模式下具有剪切条带现象。传统H-B流体在对应阶段内不再适应于全尾砂膏体流变模型，存在固、流态共存的固-流转换阶段，其范围受临界剪切速率 控制，正比于全尾砂膏体的质量浓度。依据全尾砂膏体出现固-流转换阶段的特征，提出工程流变问题应依据临界剪切速率 区别对待，以及膏体充填流变问题中不同剪切速率范围内全尾砂膏体流变模型的合理形式。
关键字: 全尾砂充填膏体；固-流转换；负斜率曲线；剪切条带；流变行为
（1. School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. State Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:Backfill paste of unclassified tailings has the characteristics of multi-scale and high-concentration, so whether typical viscoplastic rheological model was suitable for rheological behavior of paste was an important issue that needed to be studied. In this paper, the adaptability of typical H-B fluid to the paste was studied. Firstly, adaptive constraint conditions of H-B fluid were established, and rheological measurement system with data conversion method for paste were selected. Two rheological measurement modes, control shear rate (CSR) and control shear stress (CSS), were adopted to carry out the experiment. The results indicate that the flow curves of paste show negative slope for CSR mode and shear banding for CSS mode. The typical H-B fluid is not suitable for rheological model of unclassified tailings paste in special stages, and there is a solid-liquid conversion stage in which the solid and liquid phase are coexisted. The range is controlled by critical shear rate , which is proportional to mass concentration of the paste. According to the characteristics of solid-liquid conversion stage of paste, it is proposed that the engineering rheological problems should be treated differently according to critical shear rate , and the reasonable form of rheological model for paste should be considered in different shear rate ranges of backfill rheological problem.
Key words: unclassified tailings backfill paste; solid-liquid conversion stage; negative slope curve; shear banding; rheological behavior
