Abstract: To investigate the adaptability of remanufactured shields (diameter enlargement) cutting through piles of a viaduct, the cutterhead, thrust, and mucking systems of a shield are analyzed and the remanufacturing requirements of the shield are established according to construction difficulties, thereby modifying the system. The remanufactured shield is applied to Beijing metro line 12 and cuts through piles of the Xiheba viaduct. The obtained results are as follows: (1) the cutterhead adopts steel material Q345B and has an opening rate of 61%, and with the help of pilecuttingdedicated cutters and stirring wing, the abrasion, cutting, and soilconditioning performances of the cutterhead are improved; (2) the torque and thrust of the remanufactured shield meet relevant requirements with adequate allowance; (3) the anaxialtype screw conveyer is adopted, which minimizes the possibility of a conveyer jamming induced by  reinforced bar and greatly improves the mucking efficiency.

Key words: shield remanufacturing, tunneling underneath viaduct; pile cutting, adaptability