Fully mechanized longwall top coal caving technology in China and discussion on issues of further development

The paper systematically summarized the main achievements of the fully mechanized longwall top-coal caving technology in passed 20 years in China and the conclusion and understanding on the related issues. The paper provided the issues of the theoretical and technical researches to be strengthened in the next step for the fully mechanized longwall top coal caving technology. In combined with the characteristics of the top coal caving, the paper finally pointed that the coal mining with gas drainage, grouting in separated strata and strata bumping should be further researched.