Abstract:

The geomechanic data of rock mass of working roof and floor and of coal seams are an important basis to calculate and select anchor support specifications in underground coal mines. Many countries around the world are widely using geophysical methods, video endoscope of boreholes, drilling to take rock samples and analyzing rock mechanical properties to survey, to overally evaluate condition data of geomechanical coal seam and rock mass surrounding the workings. In Quang Ninh underground coal mines, drilling to take samples to determine the RQD quality of rock mass and testing for rock phisio-mechanical properties is the main method to survey the initial geological conditions for the design and use of anchors support. On the basis of summarizing foreign experiences, the authors have proposed to use a combined survey method including seismic measurement of the workings rock mass, endoscopic photography of boreholes and sampling drilling to determine the physio-mechanical properties of roof rocks to survey, evaluate the characteristics of mine geomechanical conditions to serve the calculation and selection of anchor support technical parameters and to perfect the current anchor roof passports in the underground coal mines in Quang Ninh region. The combination methods has been being applied at the roadway of stope CIII-6-1B of level +10, Vang Danh coal mine.