Preparatory Mine Research Articles

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

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.

Unitized Attachment Points of a Disk Tool for the Working Bodies of Shearers and Tunnelling Machines

An important task in the technological process of a mining enterprise is preparatory mine working performance, as effective operation of an entire mining complex depends on rate and quality of drilling. Therefore, the main factor affecting the performance of the process of underground mining is the correspondence of design and operating parameters of the working bodies of tunnelling machines to mining and geological conditions. The underground mining operations showed that rocks with a strength f ≤ 10 and high abrasiveness are to be destroyed with disc tools, providing higher strength, wear-resistant parameter and low dust formation in comparison with cutters. The usage of disk tools on the working bodies of tunnelling machines of selective action is a poorly studied task and requires special research of the questions of destruction, crushing and loading of rocks at reverse working modes. It has been established that researches aimed at design development of an attachment point of a disk tool for arrow-type working bodies of a tunnelling machines is an urgent scientific task. The original technical solutions for the design of the attachment points of disc and cutter tools are proposed to improve the processes of cutting of working bodies in the face massif, dust suppression, sealing and mounting-dismounting operations at the operation of shearers and tunnelling machines.

The influence of rock interlayer location on the stress-strain state of the rock massif near the underground mine

The results of a numerical study of rock deformation near the preparatory mine working during underground mining of coal seams of a complex structure are presented. The evaluation of the stress-strain state of rocks with the location of rock interlayer within the coal seam is performed: in its upper, middle and lower parts.

Studying the stability of mining operations under the conditions of deep mines

Purpose. Study of the sustainability of mining in the conditions of deep mines for the development of solutions to improve the safety of miners. Method. A comprehensive research method is used, including the analysis of publications, laboratory studies on models of optical and equivalent materials, the mining experiment and the processing of experimental data. Results. It has been established that when determining the size of lateral rocks displacements in reservoir preparatory workings when protected by compliant structures, their rigidity at constant load can be considered variable in time, until complete compression of the pliable support. When p rotecting the workings with the pillars of coal, the change in their rigidity occurs in a linear relationship Scientific novelty. When studying the stability of mine workings in deep mine conditions, it is proposed to evaluate the effectiveness of methods used to protect reservoir development workings by the approximation value of the haulage contour, taking into account changes in the rigidity of security structures while maintaining the output behind the lava. Practical meaningfulness. When working on sloping and steep seams at great depths, one should focus on protecting reservoir haulage drifts with wide pliable supports or laying out of the space developed, as a way to control the roof in the longwall, which will keep the local preparatory mine workings and increase the safety of mining operations.

Solution to a spatial problem in elasticity theory for a preparatory mine working

Solution to a spatial problem in elasticity theory for a preparatory mine working