粗骨料膏体低温流变性能及回归模型

来源期刊:中南大学学报(自然科学版)2020年第12期

论文作者:尹升华 刘家明 陈威 邵亚建 吴立波 王筱添

文章页码:3379 - 3389

关键词:粗骨料;低温;膏体;流变特性;回归模型

Key words:coarse aggregate; low temperature; paste; rheological behavior; regression models

摘    要:以金川某矿全尾砂、废石和棒磨砂为实验材料,采用全面实验设计法,研究温度、尾骨比(全尾砂、废石和棒磨砂质量比)和静置时间对全尾砂粗骨料膏体流变特性的影响规律,并构建关于温度、尾骨比和静置时间的流变特性回归模型。研究结果表明:全尾砂粗骨料膏体流变曲线符合H-B模型;屈服应力随温度降低而增加,随静置时间延长和全尾砂质量分数增多而增加;H-B黏度随温度的变化受尾骨比影响,当尾骨比分别为5.0:2.5:2.5和6.0:2.0:2.0时,H-B黏度随温度升高而逐渐降低;当尾骨比分别为7.0:1.5:1.5和8.0:1.0:1.0时,H-B黏度随温度升高先上升后下降;流动指数受温度、尾骨比和静置时间影响不大;在尾骨比分别为7.0:1.5:1.5和8.0:1.0:1.0条件下,随着温度升高,全尾砂粗骨料膏体由屈服假塑性体转为宾汉姆流体再转为屈服膨胀体;回归模型表明屈服应力与温度、静置时间和骨料比(细骨料与粗骨料质量比)分别呈负指数函数、二次函数和幂函数关系;H-B黏度及流动指数随骨料比不同,均为分段函数;影响屈服应力、H-B黏度和流动指数的因素权重由大到小依次为骨料比、温度和静置时间。

Abstract: Taking unclassified tailings, waste rock and rod-mill sand of mine in Jinchuan as the experimental materials, comprehensive experimental design method was adopted to study the influence of temperature, tailings-aggregate ratio(mass ratio of unclassified tailings to waste rock and rod-mill sand) and healing time on the rheological properties. Based on the experimental data, rheological characteristic regression models of temperature, tailings-aggregate ratio and healing time were constructed. The results show that rheological curve of unclassified tailings paste with coarse aggregate conforms to the H-B model. The yield stress increases with the decrease of the temperature, while it increases with the increase of the healing time and unclassified tailings mass fraction. The effect of H-B viscosity with temperature is affected by the tailings-aggregate ratio. When the tailings-aggregate ratio are 5.0:2.5:2.5 and 6.0:2.0:2.0, respectively, H-B viscosity decreases with the increase of the temperature. However, it increases firstly and decreases with the increase of the temperature at tailings-aggregate ratio of 7.0:1.5:1.5 and 8.0:1.0:1.0, respectively. Flow index is not affected by temperature, tailings-aggregate ratio and healing time. Under the same conditions, when the tailings-aggregate ratio are 7.0:1.5:1.5 and 8.0:1.0:1.0, respectively, the paste changes from yielding pseudoplastic to Bingham fluid and then to yield expansion with the increase of temperature. The regression models show that yield stress has negative exponential function, quadratic function and power function relationship with temperature, healing time and fine-coarse aggregate ratio(mass ratio of fine aggregate to coarse aggregate), respectively. The flow index and H-B viscosity are piecewise functions at different fine-coarse aggregate ratio. The order of influencing yield stress, H-B viscosity and flow index are tailings-aggregate ratio, temperature and healing time.

相关论文

  • 暂无!

相关知识点

  • 暂无!

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号