Abstract:  Presently, shield segment reinforcement skeleton is mainly welded by human, resulting in high labor intensity, poor welding environment, unstable welding quality, and low welding efficiency. As a result, an automatic welding method is proposed to replace manual welding. First, the application status of automatic welding system in other fields is presented. Second, the specific issues to be solved in realizing automatic welding of reinforcement skeleton are analyzed. Finally, based on the twostep method and matching with automatic welding production line and fixture, the automatic welding of the reinforcement mesh can be completed, and then the automatic welding of the whole reinforcement skeleton can be realized. Considering the economy and flexibility of equipment, CO2 gas shielded welding is adopted. The results show the following: (1) The reinforcement skeleton automatic welding system has the characteristics of low requirements for power system, uniform and controllable welding quality, and safe and reliable system. (2) The welding environment is improved, the labor intensity is lowered, and the welding quality of the reinforcement skeleton is improved.

Key words: shield tunnel segment, single reinforcement mesh, reinforcement skeleton, automatic welding