Underground concrete structures are affected by groundwater, the effects of which are different from those of stress environments experienced by ground engineering concrete structures. This study experimentally and theoretically investigates the mechanical behavior, permeability evolution, and deformation failure mechanism of lining concrete under pore water pressure. Results show that an increase in pore water pressure promoted the coupling of seepage and stress fields in concrete. This caused the microcracks to propagate further, which led to a decrease in concrete strength and elastic modulus. Through triaxial compression infiltration, the concrete successively underwent initial compaction, linear elastic deformation, and nonlinear deformation after yielding. Accordingly, its permeability exhibited three trends: gradual decrease, stable development, and a sharp increase. The change in permeability was closely related to the number of pores and the development of microcracks in concrete. The concept of primary pore strain was proposed according to the characteristics of deformation and failure. Moreover, a triaxial compression infiltration constitutive model was derived for concrete based on the principle of effective stress. This model considers the influence of pore water pressure and the initial compaction characteristics. This study can be used to guide the design of lining concrete structures in underground engineering.

地下混凝土结构受地下水影响，其影响不同于地面工程混凝土结构所经历的应力环境。本研究从实验和理论上研究了孔隙水压力下衬砌混凝土的力学行为、渗透性演变和变形破坏机制。结果表明，孔隙水压力的增加促进了混凝土中渗流场和应力场的耦合。这导致微裂纹进一步扩展，从而导致混凝土强度和弹性模量下降。通过三轴压渗，混凝土依次经历初始压实、线弹性变形和屈服后的非线性变形。因此，其渗透率呈现出三种趋势：逐渐下降，稳步发展，大幅增长。渗透率的变化与混凝土中孔隙的数量和微裂纹的发展密切相关。根据变形破坏的特点，提出了原生孔隙应变的概念。此外，基于有效应力原理，推导了混凝土的三轴压缩渗透本构模型。该模型考虑了孔隙水压力和初始压实特性的影响。该研究可用于指导地下工程中衬砌混凝土结构的设计。此外，基于有效应力原理，推导了混凝土的三轴压缩渗透本构模型。该模型考虑了孔隙水压力和初始压实特性的影响。该研究可用于指导地下工程中衬砌混凝土结构的设计。此外，基于有效应力原理，推导了混凝土的三轴压缩渗透本构模型。该模型考虑了孔隙水压力和初始压实特性的影响。该研究可用于指导地下工程中衬砌混凝土结构的设计。