中文摘要：

土压平衡式盾构隧道施工过程中，掘削面的支护压力严重影响着掘削面前方土体稳定性和变形。从理论上分析了掘削面前方土体的应力状态，并将其分为5类，根据支护压力的大小判定前方土体的稳定性。建立了三维有限差分模型，采用数值模拟的方法研究了掘削面支护压力与变形的关系。研究表明，在卸载情况下掘削面的支护压力与变形关系曲线具有抛物线特征，在加载情况下掘削面的支护压力与变形关系曲线具有双曲线特征，曲线的具体形态则与地层条件等因素有关。研究结果可为土压平衡盾构施工过程中支护压力的确定提供参考。

英文摘要：

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.