Development and implementation of active and combined support types for sections of mine workings exposed to bearing pressure

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Purpose. The research aims to develop and substantiate an effective technology for supporting mine workings in conditions of complex geomechanical and hydrogeological factors based on the analysis of data on the border mass strain state, the effectiveness of the supports used, as well as the behavior of materials and structures in the process of operation. Methods. The research includes the use of endoscopic surveys of wells to diagnose the border mass for the purpose of identifying fractures, cleavages and other zones of weakening. The tests are conducted on the roof-bolting support including AK01-21N(U) and AK01-30PN rope bolts with a tension of up to 100 kN. Two-component resin (15 liters per blast-hole) and DAK-1-500 N resin capsules are used for complete filling of the blast-holes. In addition, the properties of MasterRock STS 1510 shotcrete support are studied with dynamic strength control. Findings. The border mass deformations have been revealed, including fracture opening up to 1.6 m, caused by the pre-sence of ore inclusions. The use of roof-bolting support with full filling of blast-holes with two-component resin and resin capsules has shown high efficiency. The AK01-30PN rope bolts with a tension of up to 100 kN have provided significant increase in the mass stability. MasterRock STS 1510 shotcrete has shown satisfactory strength characteristics. Minor fractures have been detected that do not influence the overall stability of the mine workings. Originality. The patterns of the border mass deformation behavior under conditions of complex geomechanical factors, including zones of fracturing and local weakening caused by ore inclusions, have been revealed and characterized. It has been found that complete filling of blast-holes with two-component resin and resin capsules for reinforcing rope bolts provides a significant increase in the mass stability. The integrated use of roof-bolting and shotcrete support has proven to be effective in reducing the impact of water inrush and increasing the strength characteristics of mine workings. Practical implications. The developed technology for supporting mine workings using rope bolts with tension up to 100 kN and full filling of blast-holes with two-component resin can be implemented at mining enterprises, which will increase the stability of mine workings and safety of operations in conditions of complex geomechanical factors. The results of endoscopic diagnostics and monitoring of the border mass deformations provide a tool for timely identification of weakening zones and taking measures to strengthen the support, contributing to increased efficiency during mine working operation.