Abstract: With the East Mining Workshop of Daye Iron Mine at a transition from deep open-pit to underground mining as the project background, considering the particularity of the appearance of stope ground pressure and the complexity of workings deformation law, several means were used in the systematic study of the microscopic characteristics and preparatory workings deformation law at a transition from deep open-pit to underground mining, including in-situ macroscopic survey, testing of wallrock loosening circle, multi-point displacement meter monitoring and monitoring of mining dynamic stress. The main conclusion achieved is that it is of great guidance significance to determine the support parameters of the bolting & shotcrete net of preparatory workings and to optimize the extraction sequence, which is of reference value to similar mines.

Key words: Transition from deep open-pit to underground mining, Ground pressure appearance, Workings deformation law, Testing of mining dynamic stress