(1. School of Earth and Environment，Anhui University of Science and Technology，Huainan，Anhui 232001，China；2. State Key Laboratory for Geomechanics and Deep Underground Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221008，China；3. Anhui Huizhou Institute of Subterranean Calamity，Hefei，Anhui 230088，China)
Abstract：The three-dimensional DC method and technology for detecting overburden failure are introduced. Through several bores drilled in the top and floor rock of the coal seam in laneway，the detecting section between two bores is formed. Then through 64 poles fixed in different location of bores，the characteristics of the electric field in the top rock of different periods can be surveyed according to the mining plan. Through 3D inversion，the rock¢s resistivity of detecting area can be gained. So the changing characteristics of overburden distortion and failure from overtaking stress of mining to stable failure of anaphase can be analyzed and researched comprehensively. It provides effective technical parameters for safety production of mine. During the detecting application to overburden failure by 3D electrical method between two bores in Huainan Mine，28 groups of data are obtained continuously. The dynamic developing characteristics of overtaking stress and rock¢s distortion and destruction because of mining are analyzed and given. The height results of caving zone and fractured zone are inosculate with the calculating value according to the mining regulations under water，railway and building. The results of application show that the detecting technology by 3D electrical method between two bores has several merits，such as low cost，accurate results and dynamic detecting characteristics，and so on，compared with the traditional drilling method from ground and other detecting methods in mine. The independent and innovative technology has remarkable application and extending values in similar mines.
