Control technology and its application of roadway side wall formed by gangue in gob-side entry retaining formed by roof cutting and pressure releasing

Based on the principle of gob-side entry retaining with roof cutting and pressure releasing, the formation mechanism of roadway side wall formed by gangue was analyzed, and the motion characteristics of the roof was discussed by establishing the structure model of surrounding rock. According to the field measured data, the process of the gangue movement was divided into two stages, including rapid collapse stage and slow compaction stage, and then, the interaction relationship between the gangue and the supporting structure at each stage was clearly obtained. Besides, a control ideal, combining static and dynamic in the horizontal direction and extensible at the vertical direction to relief pressure, was put forward to lateral supporting structure base on the motion characteristics of the roof and the gangue. At last, three different control structures were proposed in view of different mining height, and the control system was established, which has been proved to be of good practicality in engineering site.