Abstract: At present, the turning radius of tunnel boring machine(TBM) is restricted. Hence, a new type of propulsion system which can realize ultrasmall radius turning of TBM is designed. Firstly, the structure composition and working principle of the propulsion system are described, the mathematical model of propulsion system is established, and the kinematic performance of the system is analyzed by means of analytical method. And then, according to the actual design load, the operation condition of the oil cylinder of the propulsion system when the TBM cutterhead breaks rock is simulated and analyzed by Adams so as to verify the theoretical feasibility of the scheme design. Finally, the propulsion system is applied to Wendeng pumped storage power station project in Shandong. The applicable results show that the smallturning radius (30 m) of TBM equipped with the new propulsion system can be achieved, and the performance indices of practical engineering application can be met.

Key words: tunnel boring machine(TBM), propulsion system, smallturning radius, parallel mechanism, Adams calculation