This study analyzed the interaction between sequentially installed combined support systems and the surrounding rock.Six distinct forms of elastic-brittle-plastic rock masses with reinforcement were analyzed,along wit...This study analyzed the interaction between sequentially installed combined support systems and the surrounding rock.Six distinct forms of elastic-brittle-plastic rock masses with reinforcement were analyzed,along with the critical displacements that governed their transition behaviors.Virtual support pressure was introduced to assess the spatial influence of the tunnel face.It was determined by integrating the longitudinal displacement profile with the proposed ground characteristic curve solutions under various ground conditions.Considering the timing of support installation,the support-rock interaction was divided into three phases.A method was presented to determine the evolution of this interaction based on critical displacements.An analytical approach was further proposed to describe the complete process of support system-rock interaction using displacement coordination.The analytical results are validated against numerical simulations and field measurements,and the method's advantages are demonstrated through comparisons with existing models and the convergence-confinement approach.Finally,the effects of surrounding rock and support parameters are examined.The results indicate that residual cohesion,the friction angle of reinforced ground,and reinforcement thickness strongly influence tunnel behavior.Additionally,increasing the stiffness or advancing the installation of secondary support substantially raises secondary support pressure.展开更多
基金Projects(52578456,52208382)supported by the National Natural Science Foundation of ChinaProject(SKLGP2023K015)supported by the Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology),China。
文摘This study analyzed the interaction between sequentially installed combined support systems and the surrounding rock.Six distinct forms of elastic-brittle-plastic rock masses with reinforcement were analyzed,along with the critical displacements that governed their transition behaviors.Virtual support pressure was introduced to assess the spatial influence of the tunnel face.It was determined by integrating the longitudinal displacement profile with the proposed ground characteristic curve solutions under various ground conditions.Considering the timing of support installation,the support-rock interaction was divided into three phases.A method was presented to determine the evolution of this interaction based on critical displacements.An analytical approach was further proposed to describe the complete process of support system-rock interaction using displacement coordination.The analytical results are validated against numerical simulations and field measurements,and the method's advantages are demonstrated through comparisons with existing models and the convergence-confinement approach.Finally,the effects of surrounding rock and support parameters are examined.The results indicate that residual cohesion,the friction angle of reinforced ground,and reinforcement thickness strongly influence tunnel behavior.Additionally,increasing the stiffness or advancing the installation of secondary support substantially raises secondary support pressure.