Mining-induced stress characteristics and fracture evolution law of over one kilometer deep Pingdingshan coal mine
ZHANG Jianguo
Abstract：To investigate the mining induced stress characteristics and cracks evolution law of gob-side entry retaining in the deep mine over one kilometer,the Ji14-31050 mining face of the No.12 mine of the Pingdingshan Coal Mining Group was studied by field in-situ monitoring and three-dimensional numerical simulation.The results show that the mining-affected area of roadway with an above one kilometer depth is larger than of tunnel with shallow depth.The overall affected area is about 70 m.The peak stress appears 10 to 30 m away from mining face.Borehole stress and anchor stress show staged evolution features.The fracture fractal dimension increases rapidly and maintains stable growth within 70 m away from the mining face.Fracture zone group formed by the perforation of the initial fracture zone and the mining fracture can be observed easily.Numerical simulation shows that 25 meters away from two sides of the goaf and upper part of the filling body along the gob present stress concentration,and their factors are 1.43 and 1.65.For the above one kilometer roadway in the Pingdingshan coal mining area,the key support area should be 70 m in front of the mining face,and the key observation area should be extended from 15 m to 20-30 m.The research will provide guidelines for some engineering practice,such as roadway support,engineering design,safe mining and mining technology optimization.
Keywords：over one kilometer deep minemining responsemining pressure appearancefracture evolutionlong-term monitoring
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 1041-1049 )