Research On The Rock-breaking Characteristic And The Layout Of TBM Gage Disc Cutter

In recent years, the TBM tunneling technology had been developed rapidly. It is widely used in many engineering projects, such as the water conservancy and, hydropower, and transportation, as well as municipal and national defense. Therefore, the demand of TBM increases significantly. The rock-breaking feature of disc cutter has become the key issues of the TBM technology, because it is directly related to disc cutter’s design and its layout method, which has direct effects on the quality and cost of tunneling. Therefore, on the basis of consulting a large number of domestic and foreign literatures, the gage disc cutter’s motion characteristic and rock-breaking characteristics and layout have been investigated in this paper. The main conclusions are as follows:(1) The disc cutter’s rock-breaking process and stress state are analyzed, and the kinematic equation of gage disc cutter is established. Finally, then the motion characteristics of gage disc cutter are analyzed obtained, which can be as a theoretically guide for the further study of rock properties and cutter layout.(2) The numerical model for rock-breaking with the gage disc cutter is established. The rock propagation process due to the effect of gage disc cutter is simulated. Then, the single-factor influence of the rock type, blade angle, blade width, the edge of the cutter installation angle and the cutterhead’s over-arc radius on the rock breaking are studied. In addition, the coupling impact of the factors on rock breaking efficiency for the gage disc cutter by orthogonal tests is analyzed.(3) The rock breaking process of the transition cutter under the different installation angle is simulated. Then, the cutting force of gage disc cutter and rock crushing characteristics are analyzed. According to the principle of minimum specific energy, the optimal installation angle is determined. The correctness and feasibility of the numerical method is verified by experimental test results.(4) An optimization model has been built established for gage disc cutters’layout. Then, the optimization layout parameters of TBM are obtained according to the Genetic Algorithm. Finally, the static performances of the cutterhead before and after the optimization layout are compared and the results show that the strength and stiffness of the optimized cutterhead have been improved. The layout of gage disc cutters plays an important role in cutterhead performances.