NUMERICAL SIMULATION OF DEPTH BIAS OVERWHELMING FORCE TUNNEL CONSTRUCTION

Based on the engineering background of Rui-Gan ExpresswayXiashan tunnel, for complex stress state oftwo-hole parallel tunnels with small spacing, the finite elementmethod is used in a small clear distance zoneof a deep tunnel under different bias conditions to simulate the stepconstruction scheme. The different excavations before and after thetunnel surrounding rock displacement and support structure and thestress variation are analyzed. On the basis of different tunnelconstruction processes, and the mechanical behavior of rock, theconcept of weak rock is proposed to show clearly the engineeringgeological conditions of weak rock tunnel control panel folder,achieved good results in actual constructions.