Dual-continuum (DC) models can be tractable alternatives to explicit approaches for the numerical modelling of multiscale materials with multiphysics behaviours. This work concerns the conceptual and numerical modelling of poroelastically coupled dual-scale materials such as naturally fractured rock. Apart from a few exceptions, previous poroelastic DC models have assumed isotropy of the constituents and the dual-material. Additionally, it is common to assume that only one continuum has intrinsic stiffness properties. Finally, little has been done into validating whether the DC paradigm can capture the global poroelastic behaviours of explicit numerical representations at the DC modelling scale. We address the aforementioned knowledge gaps in two steps. First, we utilise a homogenisation approach based on Levin's theorem to develop a previously derived anisotropic poroelastic constitutive model. Our development incorporates anisotropic intrinsic stiffness properties of both continua. This addition is in analogy to anisotropic fractured rock masses with stiff fractures. Second, we perform numerical modelling to test the dual-continuum model against fine-scale explicit equivalents. In doing, we present our hybrid numerical framework, as well as the conditions required for interpretation of the numerical results. The tests themselves progress from materials with isotropic to anisotropic mechanical and flow properties. The fine-scale simulations show anisotropy can have noticeable effects on deformation and flow behaviour. However, our numerical experiments show the DC approach can capture the global poroelastic behaviours of both isotropic and anisotropic fine-scale representations.

中文翻译：

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多尺度多孔弹性材料的各向异性双连续体表示：发展和数值建模

双连续体 (DC) 模型可以替代显式方法来对具有多物理场行为的多尺度材料进行数值建模。这项工作涉及多孔弹性耦合双尺度材料（如天然裂隙岩石）的概念和数值建模。除了少数例外，以前的多孔弹性 DC 模型假设了成分和双材料的各向同性。此外，通常假设只有一个连续体具有固有的刚度特性。最后，很少有人验证 DC 范式是否可以在 DC 建模尺度上捕获显式数值表示的全局多孔弹性行为。我们分两步解决上述知识差距。首先，我们利用基于莱文的同质化方法 s 定理来开发先前导出的各向异性多孔弹性本构模型。我们的开发结合了两个连续体的各向异性固有刚度特性。这种添加类似于具有刚性裂缝的各向异性破裂岩体。其次，我们执行数值建模以针对细尺度显式等价物测试双连续模型。在这样做时，我们提出了我们的混合数值框架，以及解释数值结果所需的条件。测试本身从具有各向同性的材料发展到各向异性的机械和流动特性。精细模拟显示各向异性对变形和流动行为有显着影响。然而，