Driving force of rockburst in deep tunnels with geological structures based on nonequilibrium evolution. Issue 5 (October 2020)

• Record Type: Journal Article
• Authors: Zhang, Y; Yang, Q; Liu, Y R; Xie, F S
• Is Part Of: IOP conference series. Volume 570:Issue 5(2020)
• Publication Date: 2020-10
• Subjects: Earth sciences -- Periodicals; Environmental sciences -- Congresses; Environmental sciences -- Periodicals; 550.5
• DOI: 10.1088/1755-1315/570/5/052053
• Languages: English
• ISSNs: 1755-1307

Abstract

Abstract: Data from field tests show that rockburst often occurs during the excavation of deep tunnels with geological structures. In the prediction and avoidance of rockburst, the driving force and evolution of the broken rock zone are more important than the final failure state. Deformation reinforcement theory is based on the minimum plastic complementary energy principle and reflects the nonequilibrium evolution for continuous entities. The residual unbalanced force of elastoplastic iteration describes the distance between the balanced and unbalanced states if the equilibrium and yield conditions cannot be satisfied simultaneously. On the basis of the unbalanced stress distribution that cannot be transferred and eliminated in the elastoplastic iteration process, the unstable zone can be distinguished and employed to predict rockburst. The distribution and direction of the unbalanced force represent the possible failure location and mode of the unstable structure. The magnitude of the unbalanced force indicates the severity of the failure. The unbalanced force criterion is compared with the traditional stress criterion through numerical simulations. Numerical simulations show that the worst condition with different geological structures can be addressed with an unbalanced force distribution. An unbalanced force can be employed as the driving force and criterion of rockburst.