Modification of the roof bolt support technology in the conditions of increasing coal mining intensity

Oleksandr Krukovskyi,Yuliia Zemlianaia,Yurii Bulich,A Bulat,O Voloshyn,Y Kryzhanivskyi,V Heyets,B Liu

doi:10.1051/e3sconf/201910900042

Abstract

The modification of the technology roof bolt supporting of mine workings in the conditions of increasing the coal mining intensity has been made. The technological schemes have been developed for the phased construction of roof bolting and frame support. This schemes make it possible to temporarily postpone the setting of frames in the mine working face, reduce the time and labour intensity for covering with a grid of the mine working arch and setting the bolts, as well as to increase the safety. The analysis of changes in the stress state of the border massif during the phased construction of roof bolting and frame support has been made. It is shown that the technology of phased construction of roof bolting and frame support ensures the maintaining a stable state of host rocks. In addition, the time between the extraction of the coal-rock mass and the setting of the primary support, as well as the distance between the face and the first row of roof bolts has been reduced to a minimum. The suggested approach makes possible to ensure the rate of preparatory mine workings development that are necessary for the intensification coal mining.

Highlights

At the present time, the combined roof bolt and frame supporting of mine workings is actively used in the coal mines of Ukraine in a wide range of geological conditions with almost no restrictions by the type, purpose, lifespan, section and location of mine workings in the rock massif [1,2,3,4]
The technological schemes have been developed for the phased construction of roof bolting and frame support, which allows to:
- postpone temporarily the setting of frames in the mine working face; - reduce the time and labour intensity for covering with a grid of the mine working arch and setting the roof bolts; - increase the degree of rocks strengthening; - increase the safety of mining operations; - increase the rate of mining operations using the existing equipment

Summary

Introduction

The combined roof bolt and frame supporting of mine workings is actively used in the coal mines of Ukraine in a wide range of geological conditions with almost no restrictions by the type, purpose, lifespan, section and location of mine workings in the rock massif [1,2,3,4]. In the mine working face, the arch support frames are set first, the grid is being hanged, but the roof bolts are to be installed with significant delays. All this violates the principles of bearing roof bolt supporting, reduces the work safety and the effectiveness of modern resin-grouted roof bolts application and the supporting as a whole [7, 8]. Therewith, it is shown that the sequence of mining operations has a significant influence on the stress values in the support elements at the completion of the mine working development

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