Analysis of cutting face support pressure for earth pressure balance shield tunneling

During the course of earth pressure balance shield tunnel construction, support pressure on the cutting face influences the stability and deformation of stratum ahead the face greatly. Stress condition of stratum ahead the face is analyzed theoretically and classified five kinds. Stability of the stratum ahead the face is judged by support pressure. Three-dimensional finite difference model is built to study the relevance of cutting face support pressure and deformation. The results show that the relation curve of cutting face support pressure and deformation is parabola in unloading conditions and is hyperbola in loading conditions respectively. Detailed configuration of the curve is relevant to the stratum conditions. The results of research can offer reference for the confirmation of support pressure during the course of earth pressure balance shield tunnel construction.