The propagation of joints and fissures, included by the frost heaving pressure arising from the water-ice phase transition is considered as frost wedging. This process is widely observed and plays a crucial role in weathering of jointed hard rocks in cold regions. Despite some fundamental results achieved in former experimental studies, a unified theoretical model is still absent, hindering a thorough understanding of this process. To further explore the mechanism of frost wedging during the freezing process, this paper firstly carries out a frost heave test on a rock block bearing a single open fissure. The results indicate that the evolution of frost heaving pressure in the fissure can be divided into four stages: sealing of the open fissure by ice wedge, ice wedge slipping, crack propagation, as well as stabilization of the ice-filled fissure. Based on the laboratory test results, a unified model for the frost heaving pressure in a single open fissure is established, which comprehensively takes into account the mechanical interaction between ice, water and rock. The model is validated by the test result, and it can reasonably describe the formation of the sealing conditions and the process of crack propagation. Fracture of the ice-rock interface near the free surface increases the likelihood of ice wedge slip, while frost wedging mainly damages geological bodies during crack propagation.

中文翻译：

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单向冻结下开放裂隙霜楔统一模型

节理和裂缝的扩展，包括水-冰相变产生的冻胀压力，被认为是冻楔。这一过程被广泛观察到，并且在寒冷地区节理硬岩的风化中起着至关重要的作用。尽管之前的实验研究取得了一些基础性的成果，但仍然缺乏统一的理论模型，阻碍了对该过程的透彻理解。为了进一步探讨冻结过程中冻楔的机理，本文首先对具有单一开放裂隙的岩块进行了冻胀试验。研究结果表明，裂隙内冻胀压力演化可分为冰楔封堵张开裂隙、冰楔滑移、裂缝扩展和充冰裂隙稳定4个阶段。基于室内试验结果，综合考虑冰、水和岩石之间的力学相互作用，建立了单一开放裂隙冻胀压力的统一模型。试验结果验证了模型的有效性，能够合理地描述密封条件的形成和裂纹扩展过程。自由表面附近冰岩界面的断裂增加了冰楔滑移的可能性，而霜楔主要在裂纹扩展过程中对地质体造成损害。