ABSTRACT
This work presents the probabilistic analysis of a wellbore with surrounding rock mass represented by Mohr-Coulomb failure criterion. Uncertainty associated with parameters of criterion is quantified from the experimental framework. Monte-Carlo simulations are performed on deterministic model dealing with analysis of wellbore. Radius of elasto-plastic boundary, radial and tangential stresses and radial displacement are determined. It is observed that probability of non-development of plastic zone is negligible for the set of input parameters. There is about 34% and 42% chance that tangential stress at E-P boundary and at wellbore periphery is less than or equal to 184 MPa and 120 MPa respectively. Probability that the strain level is less than or equal to 0.33% is found to be 36%. For a permissible value of associated risk, values of stresses and displacements which will be useful in ensuring the stability of wellbore during drilling operations.
