As porous medium,concretes of shaft lining were affected by groundwater seepage.Unified strength theory and elasto-plastic damage model were used to obtain the stress distribution of the elastic zone and plastic damage zone of shaft lining,and the analytical expression of the relationship between p0（the groundwater pressure which shaft lining can bear） and c（the plastic damage zone radius）.According to the theory of limit point of stability,the instability condition of the shaft lining water inrush was put forward.At the same time,curves were drawn between different φ（concrete porosity） and λ/E（the ratio of concrete damage softening modulus and Young’s modulus） values with p0 and c.The results show that the critical groundwater pressure p0c which the shaft lining can bear is 31.9 MPa without considering the impact of groundwater seepage in the shaft lining（φ=0）;when φ takes 0.4,p0c to 15.1 MPa,the critical groundwater pressure p0c decreases 52.7%.When λ/E takes 0.5,p0c to 30.5 MPa,when λ/E takes 2.5,p0c to 18.6 MPa,the critical groundwater pressure p0c decreases 39.0%.Thus,under considering the impact of groundwater seepage in the shaft lining,the groundwater seepage effect is very significant for the critical groundwater pressure p0c.With the increase of concrete porosity φ and the ratio of concrete damage softening modulus and Young’s modulus λ/E,the critical groundwater pressure p0c decreases%将煤矿立井混凝土井壁视为多孔介质,考虑地下水渗流作用的影响,应用统一强度理论和弹塑性损伤力学模型,推导出立井混凝土井壁弹性区和塑性损伤区应力的解析表达式,以及井壁承受的地下水压与塑性损伤区半径之间关系的解析表达式。同时绘制了不同的φ（混凝土孔隙率）和λ/E（混凝土损伤后的降模量与弹性模量之比）值与井壁承受水压p0和塑性损伤区半径c之间的关系曲线。研究结果表明：在井壁几何尺寸和混凝土强度等级不变情况下,不考虑地下水渗流对井壁的影响时（φ=0）,井壁能够承受的临界水压p0c为31.9 MPa;当φ取0.4时,p0c为15.1 MPa,井壁能够承受的临界水压下降了52.7%。当λ/E取0.5时,p0c为30.5 MPa;当λ/E取2.5时,p0c为18.6 MPa,井壁能够承受的临界水压下降了39.0%。由此可见,在考虑地下水渗流对井壁影响的情况下,地下水渗流效应和混凝土损伤软化对井壁能够承受的临界水压p0c影响十分显著,井壁能够承受的临界水压随着混凝土孔隙率φ和混凝土损伤后的降模量与弹性模量之比λ/E的增加而减小。
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