ASSESSMENT OF THE STABILITY OF THE PIT WALL USING THE CUBIC SPLINE METHOD AND THE SLOPE ANGLE OF THE PIT WALL TRAJECTORY
Keywords:
scarp slopes, fracture, stability, board, optimal board trajectory, interpolation, spline function, cubic spline method, algebraic polynomial, stability margin, angle tangent, holding and shear forces.Abstract
This paper deals with the problem of determining the optimal shape of the board trajectory and the evaluation of the stability factor, in order to ensure the stability of the boards, increasing the safety of overburden mining in the process of open-cut mining. In determining the trajectory of the boarder the method of cubic splines is used. To apply this method, the length of the base of the quarry (or ledge) is divided into arbitrary n parts and in each partial segment is constructed corresponding cubic spline function, being combined, each curve in common, gives a general curve corresponding to the profile of the trajectory of the pit wall. Then the stability margin of the pit wall is estimated, considering it as the ratio of the sum of the tangents of the angles , where , formed between the tangents to the curve at the points ,where , which serves as the trajectory of the pit wall, considering them as restraining forces, as well as the tangents of the angles , where -is the slip angle of the rock mass and the added , which are shear forces.