The Outburst can be defined as a sudden release of coal and rock accompanied by large quantities of gas into the underground coal mine workings which represents a major hazard in underground coal mines. Gas drainage has been proven to be successful in reducing outburst hazards by decreasing the in-situ gas pressure. One of aspect of gas drainage from coal seams is coal matrix volume changes. Cu...

Numerical modelling techniques are not new for mining industry and civil engineering projects anymore. These techniques have been widely used for rock engineering problems such as stability analysis and support design of roadways and tunnels, caving and subsidence prediction, and stability analysis of rock slopes. Despite the significant advancement in the computational mechanics and availabili...

The classification of natural images is an essential task in computer vision and pattern recognition applications. Rock images are the typical example of natural images, and their analysis is of major importance in rock industries and bedrock investigations. Rocks are mainly classified into three types. They are Igneous, Metamorphic and Sedimentary. They are further classified into Andesite, Ba...

This paper estimates indirect benefits of improved air quality induced by hydraulic fracturing, or “fracking”. The recent increase in natural gas supply led to displacement of coal-fired electricity by cleaner natural gasfired generation. Using detailed spatial panel data comprising the near universe of US power plants, we find that coal generation decreased by 28%. Further, fracking decreased ...

In extra-thick coal seams, mining operations can lead to large-scale disturbances, complex overburden structures, and frequent and strong strata behavior in the stope, which are serious threats to mine safety. This study analyzed the overburden structure and strata behavior and proposed the technique of confined blasting in water-filled deep holes as a measure to prevent strong rock pressure. I...

Based on differences in the permittivity of coal and limestone rock, a resonant cavity measurement technique is presented for the rapid determination of the proportions of coal and limestone in powdered mixtures. The ratio of the resonant frequency shift and the change in the transmission factor when mixed coal and limestone samples are inserted into the cavity provides a means for estimating t...

The self-potential (SP) response during hydraulic fracturing of intact Sierra granite was investigated in the laboratory. Excellent correlation of pressure drop and SP suggests that the SP response is created primarily by electrokinetic coupling. For low pressures, the variation of SP with pressure drop is linear, indicating a constant coupling coefficient (Cc) of -200 mV/MPa. However for press...

On the working face below shallow and close coal seams, there are residual pillars. The mine’s ability to operate safely is constrained by pillars’ vulnerability sudden instability powerful ground pressure disasters during withdrawal. This paper uses 31,106 of Huoluowan mine as its research backdrop employs field observation, theoretical analysis, numerical simulation examine strong dynamic loa...

For underground mining and construction, it is important to obtain a discontinuities’ model of rocks for simulations to evaluate rock stability around the working space and fluid flow in these rocks. We have developed a method using the fractal property of acoustic emission (AE) source distribution to construct a feasible crack distribution model. We confirmed the usefulness of the model throug...