This paper addresses the comparison and selection of failure criteria for in-situ rocks in borehole stability analysis. Five commonly used criteria are compared with field cases for mud weight design. The result of case studies indicates that the Mohr-Coulomb criterion, Inner Drucker-Prager criterion and Middle Drucker-Prager criterion are overly conservative, and that the Outer Drucker-Prager criterion is underestimating for designing wellbore pressure to control borehole collapse. It is concluded that the von Mises criterion is more reliable than other failure criteria and should be used for borehole collapse analysis and mud weight design. Based on triaxial test data, this paper also provides failure diagrams for some reservoir rocks. These diagrams can be used as references for borehole stability analysis when similar rocks are encountered in petroleum drilling.

You can access this article if you purchase or spend a download.