Distribution Characteristics and Impact Mechanism of In-situ Stress Field in Fold Tectonic Mining Area

The vicinity of fold structure is often the area where rock burst occurs frequently. The higher original rock stress in this area has an important influence on the occurrence of rock burst. Based on structures distribution and ground stress test results of typical fold-type mining area, the stress field type of mining area and relationship with the structures distribution are analyzed. Geo-stress field distribution of mining area is analyzed by geo-stress field inversion method and the mechanism of the rock burst in the fold-type mining area is proposed combined with the features of rock burst damage and mechanical analysis method. The results show that: the horizontal stress is the main stress in the fold-type mining area, and the maximum principal stress is perpendicular to the curve axis; the stress concentration area is usually near the axis, and with the increase of the degree of fold variation, the more obvious the regional stress concentration is, the wider the influence area is. The main impact damage of mining area is floor damage; the coupling of significantly increasing static load of surrounding rock of roadway and dynamic load caused by hard roof fracture induces the rock burst of fold-type mining area.