Study on evolution law of maximum principal deviatoric stress and plastic zone distribution in roadway surrounding rock

Abstract

The stress of surrounding rock is closely related to the distribution of plastic zone. In this paper, the maximum principal deviatoric stress is taken as the index, and the maximum principal deviatoric stress distribution of surrounding rock considering axial stress is deeply studied through theoretical analysis, and the correctness of theoretical analysis is verified by numerical simulation. The results show that: under different lateral pressure coefficients, the maximum principal deviatoric stress will show three forms: circular, elliptical and butterfly. When the lateral pressure coefficient is 1, the maximum principal deviatoric stress is a standard circular shape; with the increase of the lateral pressure coefficient, the maximum principal deviatoric stress gradually changes from circular to elliptical and then to butterfly and butterfly; under the same stress environment, there is a one-to-one correspondence between the plastic zone shape of roadway surrounding rock and the maximum principal deviatoric stress shape. The distribution of the maximum principal deviatoric stress can reflect the shape of the plastic zone to a certain extent; based on the correspondence between deviatoric stress and plastic zone, the stability of deep roadway in Kouzidong mine is analyzed, and the suggestions of roadway support control are proposed.

Keywords

• maximum principal deviatoric stress
• plastic zone
• surrounding rock control
• yield criterion
• butterfly shape destruction