Research on the energy dissipation and stress distribution characteristics of the excavated circular tunnel under high stress conditions

摘要

It is the key important problems in the world to research on rockburst disaster mechanism and control countermeasure of the deep mining tunnel under high stress conditions. The principal stresses distribution and energy dissipation were analysed according to the cases of the excavated radius, the stress level, and the non-uniform stress field of the tunnel with UDEC technique. The growth curves of the energy dissipation quantity and the energy dissipation ratio were concave with stress level increasing and the non-uniform stress field aggravating. The growth curve of the energy dissipation quantity were also concave, but the energy dissipation ratio with the excavated radius increasing was almost holding constant. The concentrated zones of the principal stress difference were extended and gradually migrated from the outside to the inside in the tunnel surroundings rock with the non-uniformstress field aggravating. When the horizontal stresses are greater than vertical stresses, the concentrating zones of principal stress difference in the roof are usually having serious consequences than these in the both sides of the tunnel.