Stability analysis of goaf underlying South-to-North water transfer project

Goaf has been encountered in the South-to-North water transfer project as a difficult geotechnical problem. The special problems are challenged with engineering construction over the goaf because of the complexity of geotechnical characters. The evaluation methods of the goaf stability was put forward on the characteristics of South-to-North water transfer project and the basic situation of Jiaozuo Coals, the influences of goaf are analyzed under the channel load, and the maximal disturbed depth of the channel foundation was found; Then the goaf stability in Fengying Coal Mine is studied with the application of 2D elastic-plastic FEM - ANSYS soft in the paper, the stability of goaf was judged by the numerical simulation and evaluation criterion of stability under additional load. The distortion and deformation caused by channel load on the goaf are satisfied to the required standard of engineering construction is obtained.