Study on Failure Characteristics and Reasonable Mining Parameters of Upward Mining of Integrated Coal Mine

Figure 10

The roof plastic zone of 3 coal roadway during the advancing period of 97308 working face. (a) Working face advancing 120 m; (b) working face advancing 160 m; (c) working face advancing 200 m; (d) working face advancing 240 m; (e) working face advancing 280 m; (f) working face advance over 280 m.