JUSTIFICATION OF THE METHOD OF DETERMINING THE LATERAL PRESSURE FACTOR ON THE METAL ARCH SUPPORT OF UNDERGROUND WORKINGS

Purpose. Justification and definition of the form of external load on metal arch support of underground workings, which is the main factor influencing the bearing capacity of the support. The relevance of this problem lies in the fact that, as a result of the war, metallurgical enterprises in the east of Ukraine were destroyed, which produced specialized rolled mining products used to manufacture fasteners for underground workings. As a result, mining enterprises developing mineral deposits by underground methods were forced to import rolled products of a similar profile from abroad. This is one of the reasons for the significant increase in both the cost of the fastener itself and the cost of the main product. Therefore, finding ways to reduce the metal consumption of mining fasteners with their bearing capacity unchanged is an urgent scientific and technical goal. Methodology. The research combines natural and analytical studies to determine the lateral pressure coefficient, which is the ratio of lateral loads on the mining fastening arch to vertical loads. This ratio is the main factor influencing the magnitude of bending moments in the arch body and its shape, the maximum value of which, in turn, determines the load-bearing fastening capacity. Results. As a result of the research, a dependence has been proposed that allows for specific mining and geological conditions to determine the value of the lateral pressure coefficient. A method has been proposed for determining the nature of the distribution of external load on steel arch fastenings of underground workings. This method will facilitate the development of appropriate models, on the basis of which it will be possible to propose an arch shape that maximizes bearing capacity while minimizing metal consumption . Scientific novelty. An analytical dependence is proposed that allows, based on in-kind measurements of the curvature of a real arch of a metal support, to determine the value of the lateral pressure coefficient, which is the main factor influencing the deformation capabilities of the support itself. Practical significance. The proposed method, which for specific mining and geological conditions based on the known distribution of external load, determined on the basis of the method created for the metal arch fastening of the capital extended workings, allows for determining such a form in which the costs of imported rolled mining will be minimized. Key words: lateral pressure factor, mining arch support, underground workings, bending moment, stress-strain state, methodology