Ye. Kozii1
Development of a complex methodology for forecasting the stability of coal-bearing rocks, taking into account the whole existing array of geological-geophysical and mining-technological information, which can and should be used in the design of new coal producing enterprises and existing mines.
The proposed complex method for forecasting the stability of coal-bearing rocks involves the sequential implementation of three interrelated stages: 1) calculation of the compressive and tensile strength of rocks (layered and in massive) for 20-meter roof interval and 10-meter subsoil coal seams. 2) selection and quantitative assessment of weakened cavernous-fractured zones in well logs according to standard and acoustic logging and geological documentation; 3) characteristics of the active roof of coal seams in terms of stability, load-bearing properties and controllability.
Research, including the study of physical and mechanical properties and stability of coal seams is mandatory in the geological and economic assessment of coal deposits.
Constructed maps of roof stability of clearing workings containing the information on the area of development of a false roof and cavernous - cracked zones, about stability of a direct roof, about type of the main roof on loading properties, and consequently about a class of controllability of an active roof. There are a source materials that allow to make a choice of ways of to manage the roof, to justify the passports of fastening, substantiate support patterns, ensure workplace safety, improve planning and technical and technological support of mining operations in existing mines, create the most rational schemes and procedures for working coal seams in the design of new coal mining enterprises.
The use of the proposed complex of geological and geophysical methods allows to determine in as much detail and quickly the physical and mechanical properties of coal-bearing rocks in their natural occurrence continuously throughout the geologic cross-section of each well drilled in the field and obtain conditional geological information to predict the behavior of rocks.
The use of the proposed methods allows at least 5-6 times to increase the initial data, which significantly increases the reliability of the forecast. This method meets all the requirements of regulatory documents governing the study of mechanical properties of coal-bearing rocks and coal in the geological and economic assessment of coal deposits and the design of new mine workings at existing enterprises.
Keywords: forecasting stability method, coal-bearing rocks, geologic cross-section, tensile strength