Optimal Support Solution for a Soft Rock Roadway Based on the Drucker–Prager Yield Criteria

Through theoretical calculation, the stress and deformation of surrounding rock can be analyzed, providing guidance for support design optimization soft roadways. In this paper, solutions both optimal pressure allowable maximum displacement are derived from Drucker–Prager (DP) yield criteria steady creep criterion expressed by third invariant deviator stress. The DP with different parameters is compared analyzed an engineering example. Then, based on calculation results effects long-term strength, cohesion, internal friction angle plastic zone radius roadway discussed. show that solution roadways not only reasonably reflect intermediate principal but also used to compare discuss influence results. higher strength a is, smaller force larger is. When calculated ensure does exceed displacement, maintain stability without support. With increase in cohesion or rock, decreases gradually reduced degrees. use grouting other means improve effectively reduce save costs. This new consider criteria, enabling become easier determine. It has wider range applications, better demonstrate potential rock.