摘要
为加深对端部放矿矿岩颗粒流动机理的认识,采用颗粒离散方法,通过均匀分布的球形颗粒描述矿岩块构成,设计了具有矿岩散体细观性质的三维无底柱数值模型,进行了放出体流动特性细观分析。利用接触力学方法计算矿岩流动过程中颗粒间的接触力和力网分布特征,计算结果表明:①放矿过程中颗粒间接触力与平均接触力的比值f不受放矿的影响,肯峰值约等于1,在f>1时服从幂函数关系,f<1时呈负指数关系;②颗粒内长度L大于3个颗粒数的力链概率服从e指数关系,一次放矿中力链较长的概率略有降低,但在任意时刻,均随着力链长度的增加而迅速下降;③放矿的全过程中,f∈[1,2]时接触力随出矿次数的增加而线性下降,但f>2时接触力不受放矿影响。
In order to deepen the understanding on the mechanism of ore-rock particle flow at the side ore-drawing, a three-dimensional numerical model without pillar was designed by using discrete element method and describing the composition of ore-rock block by uniformly distributed spherical particles, and the micro-analysis on the flow characteristics of ore-rock bulk was carried out. The contact force and force network distribution between particles in the process of ore-rock flow were calculated by the contact mechanics method. The results showed that:① the ratio of contact force between particles and average contact force in the process of ore drawing is not affected by the ore drawing, and its peak value is about 1, which obeys power function when f > 1 and negative exponential function when f < 1;and ② the probability of force chain in which the inner length L is longer than 3 particles obeys the exponential relationship e. The exponential relationship shows that the probability of longer force chain in primary drawing decreases slightly, but it decreases rapidly with the increase of the length of force chain at any time.③ in the whole process of ore drawing, the contact force decreases linearly with the increase of the times of ore drawing when f∈[1,2], but the contact force is not affected by ore drawing when f> 2.
作者
韩连生
杨宇江
Han Liansheng;Yang Yujiang(Exposed Branch,Gongchangling Mining Corporation,Mining Company of Ansteel Group Corporation,Liaoyang 111008,China;School of Mining Engineering,University of Science and Technology Liaoning,Anshan 114051,China)
出处
《金属矿山》
CAS
北大核心
2019年第4期36-40,共5页
Metal Mine
关键词
崩落法
颗粒流
接触力
力链
Caving method
Granular flow
Contact mechanics
Force chain
