According to the analysis of the classification of more than 20 mining methods at home and abroad, there is also a development process for mining method classification. As far back as the beginning of the 20th century, American scholars began to classify mining methods with the mining order and mining method as the main classification principles. The main disadvantages of the classification method in this period are: the classification characteristics are not obvious, not uniform, the boundaries between some methods are unclear, and there are repetitions. With the development of science and the advancement of mining methods, the classification of mining methods is gradually developing and improving. In the late 1930s, the US Bureau of Mining, based on the principle of maintenance of mining face, proposed the classification method of four types of natural support face mining method, artificial support face mining method, caving mining method and joint mining method. A step. After the 1950s, many mining scholars in the Soviet Union successively proposed the classification of mining methods based on the maintenance methods of the goaf in the mining process, so that the classification of mining methods gradually became uniform. After entering the 1970s, especially in recent years, the classification of mining methods has been gradually based on the principles of simplicity and practicality, based on the state and maintenance methods of the goaf during the mining process, and the mining that is rarely used now has been deleted. The method and the unclear joint mining method are highly broadly classified into three categories: the empty field mining method (natural support mining method), the filling mining method (artificial support mining method) and the caving mining method.
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