China is the world's largest coal-producing country and its coal production was 3.57 billion ton in 2014, of which underground longwall mining accounts for more than 85%. China has achieved great progress in ground control of underground mining. Many theories are well applied to coal mining, such as the "voussoir beam" theory for analyzing the roof breaking law and shield support capacity, the "key strata" theory for controlling the surface subsidence, the dynamic load theory for determining supports capacity in large-cutting-height mining and top-coal caving mining and the coal wall shear failure theory for high strength mining. The maximum capacity of self-developed two-leg and four-leg shield support reaches 21000KN, which realized the strata control of working face in large-scale mining. The backfilling mining technique for controlling surface subsidence is basically mature. Strengthen the research on ground control theory of extremely-thick coal seam mining, gob-side entry retaining technique in top-coal caving mining, multiple coal seams mining and deep coal seam mining are the main directions of future development of ground control theory and technique in China's coal mine.


Since 2010, China has become the largest energy consumption country in the world with a total of 38.52 billion tons, accounting for 22.4% of the world's total energy consumption. Coal accounts for 76% of energy consumption in China [1]. China’s coal production reached 3.66 billion tons in 2013, however, it decreased by 2.5 percent in 2014 than the amount in 2013, which is the first negative growth of China's coal production since 2000. Nevertheless, China's coal production accounts for about 48 percent of world coal production, of which 85 percent comes from underground mining, so underground mining plays an important role in China. Nowadays fully mechanized longwall mining has become the main method for underground coal mining in China, but there are some differences on the specific mining method because of the influence of coal seam thickness, inclination and many other factors.

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