A mine has a 6m diameter vertical ventilation shaft. Calculate the radial, circumferential and shear stresses 0.2m into the rock at the north point (A) for a depth of 2500m below surface. Draw a simple sketch of the shaft showing the stresses, directions, the point A with proper labels. The principal in situ horizontal stress in the north-south direction is equal to half the overburden stress, and the principal in situ horizontal stress in the east- west direction is twice the overburden stress. The unit weight of the rock y is 0,025 MN/mº. The modulus of elasticity of the rock E is 50 GPa, and Poisson's ratio for the rock v is 0,25. Assume that the rock behaves elastically.

Answer rating: 100% (QA)

Solution Refrigouted Air Tai lic hisw R mk 25 1 hi x Ai R3 R R5 H L Kp A L R Ki A L Kp A 0 0003m ... View the full answer