The rupture of hydrogels and swellable elastomers involves large deformations, and there exists a large literature devoted to their experimental characterization including methods for measuring and enhancing fracture toughness. Analytical investigations of the fracture of hydrogels have recognized the importance of large deformations and the contributions of liquid flow, but they have largely been restricted to plane-strain formulations that ignore through-thickness effects. In this paper, boundary–initial value problems for cracked specimens are solved in plane-strain and three dimensions for both permeable and impermeable boundary conditions and various rates of loading. The transient stress, strain and chemical potential fields near the crack tip/front are found to be notably different than the asymptotic solutions of linear poroelasticity and large deformation plane-strain formulations. The energy release rate is computed using a poroelastic path-independent integral ($J^{\ast }$), and generally that also is a function of the liquid flow. It is shown for moderately thin three-dimensional specimens that liquid flow is largely in the out-of-plane direction under permeable boundaries and largely in-plane for impermeable boundaries; thus, liquid flow makes larger contributions to the energy release in the latter. In agreement with experiments, the energy release rate tends to be larger at higher loading rates due to the contributions of liquid flow. Finally, criteria for crack growth based on the critical stretch ahead of the crack are adopted to predict the critical energy release rate as a function of solid volume fraction, and the possibility of a non-monotone dependence of energy release on solid volume fraction is uncovered. The methods presented in this paper can be utilized to analyze a wide variety of problems in the rupture of hydrogels including applications to soft tissues and fibrous gels.

水凝胶和可膨胀弹性体的破裂涉及大变形，并且存在大量文献致力于它们的实验表征，包括测量和提高断裂韧性的方法。水凝胶断裂的分析研究已经认识到大变形的重要性和液体流动的贡献，但它们在很大程度上仅限于忽略全厚度效应的平面应变公式。在本文中，裂纹试样的边界初值问题在平面应变和三个维度上求解，包括渗透和不渗透边界条件以及各种加载速率。短暂的压力，发现裂纹尖端/前沿附近的应变和化学势场明显不同于线性多孔弹性和大变形平面应变公式的渐近解。能量释放率使用多孔弹性路径无关积分（${Ĵ}^{*}$)，通常这也是液体流量的函数。对于中等厚度的 3D 试样，液体流动主要在可渗透边界下的平面外方向，而对于不可渗透边界，则主要在平面内；因此，液体流动对后者的能量释放做出了更大的贡献。与实验一致，由于液体流动的贡献，在较高的加载速率下能量释放速率往往更大。最后，采用基于裂纹前临界拉伸的裂纹扩展标准来预测作为固体体积分数函数的临界能量释放率，揭示了能量释放对固体体积分数的非单调依赖性的可能性.