FSI Analysis Of The Cutterheadand The Soil In Chamber For EPB Shield Machine

The earth pressure balance (EPB) shield tunneling machine is an important technical equipment for infrastructure projects, resource development and national defense. Dynamic balance of earth pressure in chamber is the key for tunneling safely and efficiently, pressure imbalance will lead to serious engineering accidents such as surface subsidence. A clear understanding of distribution of earth pressure in chamber and the establishment of the complete mechanical model provides a basis for the precise control of earth pressure in chamber.To overcome the problem mentioned above, in this paper, FSI(fluid and solid interaction)numerical simulation of the soil in chamber and the cutterhead is developed, and the overall distribution of earth pressure in chamber under the disturbance of the cutterhead is obtained. Relationship between the pressure on the excavation face and the pressure on the chamber board is studied. The influence regularities of the operating parameters, the material parameters of the soil and the structure form of cutterhead on the distribution of earth pressure in chamber are analyzed. The key factors influencing on the balance of earth pressure in chamber are determined. Based on the analysis results, the appropriate places of cutterhead to install stirring bars are proposed.The stress distribution of cutter head is obtained based on the result of FSI numerical simulation as well. The cutterhead torque imposed by soil in chamber is analyzed. The influence of the working parameters, the material parameters of the soil and the structure of cutterhead on the cutterhead torque is analyzed. The functional relations between the parameters (rotational speed of cutterhead, soil viscosity and cutter opening ratio) and cutterhead torque are established separately.