STABILITY ANALYSIS OF SOFT ROCK SURROUNDING TUNNEL BASED ON HOEK-BROWN STRENGTH CRITERION

Due to the long-term geological and structural forces, there are a large number of weak fracture zones in the underground rock mass. Tunnel excavation through this area is prone to large deformations and even accidents such as landslides. This paper uses the method of TGP advanced geological prediction combining with the investigation of the surrounding rock of the face. It carries out the detailed geological survey of the undisturbed rock mass in the tunnel face and the front. It obtains the Hoek-Brown parameters of the rock surrounding the tunnel. The paper uses the FLAC^3D numerical simulation method to analyze the stability of surrounding rock in the crushing zone under the given supporting conditions. It compares the numerical results with the field monitoring data to verify the correctness of this method. The results show that the numerical simulation results are in good agreement with the actual monitoring results. We can use this method to guide the stability prediction of unexcavated tunnels to ensure the construction safety of the tunneling process.