Development of gravity flow draw theory and determination of its parameters

The caving mining method relies on gravity to transport large amounts of caved ore and rock, therefore, the gravity flow rules are the foundation for determining or optimizing the stope parameters. The stochastic medium draw theory of gravity flow is relatively fast and easy to implement, and it can describe different shapes of the drawbody. However, the theory usually regards the drawpoint as a point without considering the width, and only a few researchers consider the determination of parameters in the stochastic medium draw theory. In this paper, the drawpoint width was taken as the move boundary based on the present characteristics of the stochastic medium draw theory, and the theoretical equations were established under the non-point drawpoint. For the determination of the parameters in the theoretical equations, a new and relatively simple method was proposed using the data of the move boundary and fall funnel, and then, a self-designed experimental model was developed. The results of physical experimental and numerical simulation showed that the theoretical equations were reasonable and the new method was viable. This study improves the applicability of the stochastic medium draw theory of gravity flow rules.