In this article we formulate and implement a computational multiphase periporomechanics model for unguided fracturing in unsaturated porous media. The same governing equation for the solid phase applies on and off cracks. Crack formation in this framework is autonomous, requiring no prior estimates of crack topology. As a new contribution, an energy-based criterion for arbitrary crack formation is formulated using the peridynamic effective force state for unsaturated porous media. Unsaturated fluid flow in the fracture space is modeled in a simplified way in line with the nonlocal formulation of unsaturated fluid flow in bulk. The formulated unsaturated fracturing periporomechanics is numerically implemented through a fractional step algorithm in time and a two-phase mixed meshless method in space. The two-stage operator split converts the coupled periporomechanics problem into an undrained deformation and fracture problem and an unsaturated fluid flow in the deformed skeleton configuration. Numerical simulations of in-plane open and shear cracking are conducted to validate the accuracy and robustness of the fracturing unsaturated periporomechanics model. Then numerical examples of crack branching and non-planar cracking in unsaturated soil specimens are presented to demonstrate the efficacy of the proposed multiphase periporomechanics model for unguided cracking in unsaturated porous media.
翻译:在本文章中,我们为不饱和的多孔多孔性介质中的非制导分解设计了一个计算多相半部位半部机械模型。 固态阶段的同一调节方程式适用于裂缝和裂缝。 这个框架中的裂缝形成是自主的, 不需要事先对裂缝表层进行估计。 作为新的贡献, 一个任意裂缝形成以能量为基础的标准, 使用不饱和的渗漏介质的极强力状态来设计。 断裂空间中的不饱和液流流以简化的方式建模, 与不饱和的液体散装介质流的非本地配制相匹配。 配制的不饱和的极易腐蚀性半部位半部位半部分解的精度在数量上实施。 两阶段操作者将相伴合的透裂现象转化为不饱和的变形质和断裂性介质的介质, 在不饱和的机体模型中进行不饱和的液流模拟。 在不饱和不饱和的模型中,正在对不饱和不饱和的土壤结构结构结构进行不振的不振的模型进行。