Thermally induced fracture is a common phenomenon for concrete and rock-like materials, which presents a significant challenge to numerical modelling. In this work, a thermo-mechanical model for mixed-mode fracture based on phase-field method is proposed. This approach overcomes the difficulties of modelling the thermally induced cracking process when it comes to complex fracture patterns. To simulate different failure modes in thermo-mechanical conditions, the model's constitutive expression includes a unified failure criterion that takes into account both tensile and shear strengths. The proposed formulation provides a length scale insensitive response for brittle materials such as rocks, although other prevalent phase-field theories for purely mechanical fracture can also be involved. The computational results of the representative examples for rock-like materials are highly consistent with prior findings. It demonstrates that the presented model can effectively reproduce the thermally induced cracking process for various cracking patterns, such as tensile, shear, and tensile-shear fractures, indicating the method's remarkable capabilities for further research.

中文翻译：

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混合模式断裂的热机械相场模型及其在类岩石材料中的应用


热诱导断裂是混凝土和类岩石材料的常见现象，这给数值建模带来了重大挑战。本工作提出了一种基于相场法的混合模式断裂热力学模型。这种方法克服了在复杂断裂模式中模拟热诱导开裂过程的困难。为了模拟热机械条件下的不同失效模式，模型的本构表达式包括一个统一的失效准则，该准则同时考虑了拉伸强度和剪切强度。所提出的公式为岩石等脆性材料提供了长度尺度不敏感响应，尽管也可能涉及其他流行的纯机械断裂相场理论。岩石状材料的代表性示例的计算结果与以前的发现高度一致。结果表明，所提出的模型可以有效地再现各种开裂模式的热诱导开裂过程，例如拉伸、剪切和拉伸-剪切断裂，表明该方法具有卓越的进一步研究能力。