Abstract: Taking the adjustment of the stope structural parameters of the Underground Workshop of Daye Iron as the engineering background, based on the data obtained in the macro-survey and the practical measurement of the displacement of the roadway surrounding rock and by adopting displacement back analysis method and FLAC software, the numerical simulation and contrast research on the active law of ground pressure both before and after the adjustment were made from the aspects of the active law of stress, the distribution characteristics of displacement field and the change regularity of plastic fractured region. The research has disclosed the basic law of the change in stope ground pressure in the large-spacing non- non-pillar sublevel caving, which is of great significance to the application and promotion of this caving method in underground metallic mines.

Key words: Large Spacing, non-pillar sublevel caving, ground pressure, FLAC numerical simulation