柔性隔离层下单漏斗散体矿岩流动规律

Flow pattern of granular ore rock in a single funnel under a flexible isolation layer

同步充填留矿法因柔性隔离层的存在,其散体矿岩流动规律突破传统放矿理论的描述范围,因此开展柔性隔离层下单漏斗散体矿岩流动规律研究对于丰富放矿学理论具有重要意义.基于相似原理建立物理试验模型,以标记颗粒刻画出放出体和松动体形态,采用高清摄像机记录试验基础数据.基于试验数据,对柔性隔离层下单漏斗放矿放出体、松动体、空腔等演化规律进行分析.最高层位矿石未放出前,放出体呈完整封闭的近似椭球体形态;放出后,放出体呈现为陀螺体.最高层位矿石产生沉降前,松动体为完整封闭的近似椭球体形态;产生沉降后,松动体形态整体上呈喇叭状,喇叭状松动体上部为指数曲线,下部为近似部分椭球体.空腔在最高层位矿石产生沉降瞬间开始形成;隔离层边界与矿石层边界相切于空腔边界,切角随着隔离层下降深度的增大而增大,至散体自然安息角后保持不变,切点位置随着隔离层下沉由中间逐渐向两侧发展至放矿终止.

Due to the existence of a flexible isolation layer the flow pattern of granular ore rock in the synchronous filling shrinkage method breaks through the description range of the traditional ore drawing theory,so studies on the flow pattern of granular ore rock in a single funnel under a flexible isolation layer have important significance for enriching the ore drawing theory. Based on the similarity principle,a physical test model was designed,by which the morphology of the draw ore body and the loosen ore body was delineated and drawn by marking particles. The basic data of testing were recorded with a high-definition camera. The evolution laws of the spatial morphology of the draw ore body,loosen ore body,and cavity during single funnel drawing under a flexible isolation layer were analyzed on the basis of these basic data. The draw ore body showed completely closed and quasi-ellipsoidal morphology before the highest horizon ore settled; but after this settlement the draw ore body was gyrostatic. Before settlement of the highest horizon ore occurred,the loosen ore body showed completely closed and quasi-ellipsoid morphology; but after this settlement appeared,the loose body shape was trumpet-shaped on the whole,with an exponential curve in the upper part and a quasi-ellipsoid in the lower part. The cavity began to form at the moment when the settlement of the highest horizon ore occurred. The isolation layer was tangent to the ore layer at the cavity boundary. The cutting angle increased with the increasing fall depth of the isolation layer and kept invariant after it reached to the natural repose angle. With the sinkage of the isolation layer,the position of the tangent point gradually changed from the center to both sides until the end of ore drawing.