Recent advancements on the variational approach to fracture for the prediction of complex crack patterns in heterogeneous materials and composite structures is herein proposed, as a result of the frontier research activities undertaken in the FP7 ERC Starting Grant project CA2PVM which focuses on the development of computational methods for the durability and the reliability assessment of photovoltaic laminates. From the methodological viewpoint, the phase field approach to describe the propagation of brittle fracture in the bulk has been coupled for the very first time with the cohesive zone model to depict interface crack growth events, for 2D isotropic and anisotropic constitutive laws, and also for 3D finite elasticity. After a summary of the key aspects underlying the theoretical formulation and the finite element implementation using a monolithic fully implicit solution scheme, an overview of the main technological applications involving layered shells, interface mechanical problems and polycrystalline materials is provided. The examples are selected to show the capability of the proposed approach to investigate complex phenomena such as crack deflection vs. crack penetration at an interface, intergranular vs. transgranular crack growth in polycrystals, and interlayer vs. translayer failure in laminates.

中文翻译：

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相场方法在异质材料和结构脆性断裂方面的最新进展。

作为FP7 ERC起始资助项目CA2PVM中开展的前沿研究活动的结果，本文提出了用于预测异质材料和复合结构中复杂裂纹模式的断裂变分方法的最新进展，该研究致力于计算方法的开发用于光伏层压板的耐久性和可靠性评估。从方法学的角度来看，用于描述脆性断裂在块体内扩展的相场方法首次与用于描述界面裂纹扩展事件的内聚力区域模型相结合，用于二维各向同性和各向异性本构关系，以及3D有限弹性。在总结了使用单片完全隐式解决方案的理论公式和有限元实现的关键方面之后，概述了涉及层状壳，界面机械问题和多晶材料的主要技术应用。选择这些实例以显示所提出的方法研究复杂现象的能力，这些复杂现象例如在界面处的裂纹挠度与裂纹渗透，多晶中的晶间裂纹与跨晶裂纹增长以及层压板的层间裂纹与跨层破坏。