摘要：Rock strength criterion is a basic subject in mining engineering and petroleum engineering. It has important guiding significances to the process of underground energy exploitation. Different rocks have different strength envelopes. Most strength criteria have only one type of envelope in π plan. Thus, these criteria cannot predict different rock strengths accurately. Most criteria consider only the hydrostatic stress and the Lode angle effects and neglect their interaction. However, based on the experimental results in this study, there is an evident interaction between the two effects. In this study, a new strength criterion is proposed considering the hydrostatic stress and Lode angle effects, as well as the effect of hydrostatic stress on the Lode angle effect. Applicable results of previous experimental data showed that the proposed strength criterion has good applicability for different rocks. Compared with other strength criteria, this criterion has the advantage of being able to adjust the strength of the Lode angle effect based on the hydrostatic stress. This advantage allows the strength criterion to show different types of strength envelopes in the π plan and to accommodate different rocks under different stress states. The effect of hydrostatic stress on the Lode angle effect of rock may be caused by the proportion of particles destroyed in the rock.
