崩落矿岩流动特性及影响因素试验研究-矿业工程.PDF

39 5 Vol. 39 No. 5 2010 9 Journal of China University of Mining T echnology ep. 2010 王洪江, 尹升华, 吴爱祥, 沈慧明 ( , 100083) : 采用 1100 的相似比进行放矿物理模拟实验, 将矿样破碎后按粒级组成分为和这2 组矿样, 进行了模拟放矿实验, 过拟合得到了放矿高度为55, 95, 145 m 时的放出椭球体; 大块 含量高的粒级组成放出体短半轴比粒级组成大20% , 但大块含量的增加导致放矿卡斗堵塞 频率增大, 粒级组成的堵塞频率为的7 倍; 此外, 矿岩孔隙当量直径越大, 细小颗粒穿流现象 越明显, 细粒含量较多的覆盖层能使矿石贫化率提高3 倍以上, 含水量也是影响崩落矿岩流动性 的重要因素, 含水率在 10% 左右的矿岩抗剪强度较大. : 崩落矿岩; 流动特性; 细颗粒; 覆盖层; 含水量 : TD 32 : A : 1000- 1964( 2010) 05-0693-06 Experimental tudy of the Factors Affecting the Ore Flow M echanism During Block Caving WANG Hong-jiang, YIN heng-hua, WU A-i xiang, HEN Hui-ming ( chool of Civil and Environment Engineering, University of cience and Technology Beijing, Beijing 100083, China) Abstract: Physical simulations at a scale of 1100 were conducted to determine the factors af- fecting ore flow during block caving . An ore sample obtained from a mining site w as crushed and divided into fractions by size. Draw ellipsoids w ere found from the experimental results by fitting data from trials at draw-heights of 66, 96 and 145 meters. T he shorter axis of the sec- ond group draw ing body w as 20% larger than for group one, due to the higher content of larger particles. T he ore-blocking frequency increases w ith an increase in large sized ore particles. The blocking frequency of a third group w as seven times that of the first group. A preferential flow of smaller particles w as observed w hen the equivalent diameter of the ore-pores w as large. Dilution increased by a factor of three w hen the fine-particle content in the covering material w as high. Water content had an important affect on the ability of the ore granules to flow . T he shear strength of the ore