Abstract: The safety risk posed by the swing structure of the propulsion beam of the tunnel boring machinecarried bolt drill because of complex stress during the construction of tunnels should be resolved. As a result, to improve the swing structure′s mechanical properties and stability, statics analysis is conducted to determine the weak positions with stress concentration and extremely uneven stress distribution. Furthermore, using the submodel method, the swing structure′s weak points are removed to increase its design space. The structure is then optimized using the topology optimization method, thereby obtaining a new topology form of the part. Finally, the stress, deformation, and vibration frequency of the swing structure before and after optimization are compared. The results show that the stress concentration of the swing structure under dangerous working conditions has been reduced, stiffness and strength of the structure have been improved to a certain extent, and vibration characteristics and structural stability of the structure have also been improved.

Key words: tunnel boring machine (TBM), TBM-carried bolt drill, tunnel support, finite element analysis, swing structure, topology optimization