| Abstract: | In this paper a bifurcation analysis of boreholes in deep rock formations under uniform stress at infinity is presented. Rock is described by the constitutive equations of a deformation theory of plasticity for rigidplastic, incompressible and cohesive-frictional material. The corresponding bifurcation problem is solved numerically by the finite element method. The evidence gained from the numerical solution is utilized to establish a simplified borehole stability analysis that combines Biot's hodograph method with a surface instability analysis. |
