3D NUMERICAL SIMULATION AND ANALYSIS OF THE EFFECT OF ENGINEERING FACTORS ON THE STABILITY OF SURROUNDING ROCK

The effect of cross-section shape of roadway of distance of working face,sequence of excavation on the stability of surrounding rock, and displacement of many sites in deep part of surrounding rock are simulated with FLAC3D in some engineering practice . The result shows that there are different mechanical effect with different cross-section shape of roadway under the same condition of surrounding rock, different deformation of different surrounding rocks, appeared on the same cross-section and the curve of horizontal displacement of surrounding rock is s-shaped with distance from working face. A maximum horizontal displacement of surrounding rock mainly occurs in a range of double diameters of the roadway in the rear of working face. The range of displacement of deep part of Ⅲ-grade surrounding rock is about 2.6～4.3m and that of Ⅳ-grade surrounding rock is 6.9～ 7.8 m. For larger cross-section of roadway in-steps an excavation is beneficial to control on surrounding rock.