Time-varying radial displacement solution in the plastic zone of the circular roadway under constant biaxial stress and analysis of rockburst prevention
The mechanical process of the elastic and plastic zone of the surrounding rock that change over time under the action of constant biaxial stress load is analyzed using the time-varying theory. A plane strain model of the circular roadway is established to obtain the elastic time-varying solution, elastoplastic time-varying solution and time-varying radial displacement solution in the plastic zone using the bilinear constitutive equations of the elastic zone and plastic zone. The results show that when the boundary movement rate of the plastic zone was relatively large, the radial displacement in the plastic zone increased with time. The larger the roadway radius, the greater the radial displacement in the plastic zone at the same moment. In essence, the time effect of rockburst is that the radial displacement in the plastic zone of the surrounding rock reaches the critical softening depth. To prevent the rockburst, the radial displacement of the plastic zone should be reduced as far as possible. The time-varying radial displacement solution in the plastic zone provides a new idea for the prevention and control of rockbursts.