INFLUENCE OF UNDERGROUND MINE PARAMETERS ON THE VALUE OF DAYLIGHT SURFACE SETTLEMENT OF UNDERMINED TERRITORY

Abstract

The article presents the analysis results of influence of shape and dimensions of cross-section, laying depth of mine, cross-section shape and dimensions of underground mine on the daylight surface settlement of undermined territory depending on the different numerical values of the soil lateral pressure coefficient of the surrounding soil. The numerical solution was obtained in an elastic setting using the computer programs «FEA» and «Stability». In the calculations, the elastic modulus of the enclosing rocks is taken equal to the dimensionless constant E /γ H = 500 (where γ; H are the rocks volumetric weight and laying depth of mine), therefore, the numerical values of the vertical displacements gained as a result of the calculations are also dimensionless. This approach is convenient for both quantitative and qualitative analysis, because not only specific values of vertical displacements are considered, but also change patterns of their values depending on changes in the numerical values of the variables of the calculated parameters. Assuming that the displacements in the linear formulation of the problem are inversely proportional to the elastic modulus, their magnitudes can be determined for any other value of E . It was established the vertical displacements of earth’s surface points located above the mine, provided that the depth of its laying is more than 15.2 m and the dimensions of the cross section are greater than 4×4 m, significantly depend on the shape of the cross section and the lateral pressure coefficient of the surrounding rock. In addition, smaller vertical precipitation of the daylight surface corresponds to an underground mine having an exotic and «non-technological» cross section in the deltoid form. Therefore, the problem arises is to obtain such an optimal cross-sectional shape of the mine that would ensure the minimum precipitation of the earth's surface. The cross-sectional shape of the mine must be as “technological" as possible according to its advancement. The subject of further research is the solution of these problems.