| This dissertation analyses the mining method and roof stability of hard-to-mine orebody. Mining of gently inclined thin and medium thick ore body with unstable roof isregarded as typical hard-to-mine ore body. This kind of ore body has occupation ration inmetallic mineral, especially, the ratio of this kind of ore body is rather large in gold ore andother nonferrous metal and it has great value of reclaim. However, this kind of ore body isextracted with common mining method difficultly and the roof control is also difficult.This dissertation puts forward new mining method which is disparted from converseand forward according to room and pillar on the basis of research in response to concretecondition of thin and medium thick ore body with unstable roof in Jinchangyu gold mine,and it utilizes the theory and method of mining engineering,rock mechanics,computersimulation,on-the-spot measurement etc. The upward incise is used as free face in thefirst layer and the bottom of room is pulled conversely. The second layer is extracted bymeans of ripping blasting forwardly. It analyses roof stability by block theory and designsroom span,site and inch of pillar etc. Moreover, the zone of roof,site and attitude offracture are detected by ultrasonic testing instrument. It makes the numerical simulation ofroof stability in the experiment by FLAC, and original scheme is modified ,adjustedaccording to analog result. In the course of mining, roof stability,acoustic emission lawof wall rock fore and after blasting and the forecasting of roof stability are monitored byacoustic emission system, therefore, this system ensures safety coal extraction of miningfield. Practice proves that the scheme of paper achieves satisfied result, and select practicalnugget safely and efficiently; moreover, it acquired good economic benefit and socialbenefit.This achievement has promotional value for hard-to-mine ore body whose conditionis analogous to this. Its economic benefit is large.
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