针对水化作用对地下工程岩体力学强度影响不明确的问题,运用岩石力学实验与数值仿真相结合的方法,以龙马溪组页岩为研究对象,通过对不同浸泡时间下的岩石进行单轴抗压实验和Abaqus有限元数值分析,探讨水化作用对页岩力学性能的影响及其破坏机理。结果表明:水化作用会削弱页岩的内聚力,从而显著降低页岩的峰值应力和弹性模量,并且随着水化时间的延长,岩石的破坏模式由脆性破坏转变为塑性破坏;同时,水化作用对页岩力学强度的劣化存在临界点,劣化后的岩石力学强度约为干燥状态下的69.19%。研究成果为理解地下工程岩体的水化力学劣化行为及指导工程稳定性评估具有重要意义。
In response to the insufficient understanding of rock mass hydration on mechanical strength in underground engineering,a combined approach of rock mechanics experiments and numerical simulation was used,with Longmaxi Formation shale as the study object.Uniaxial compression tests and Abaqus finite element simulations were conducted on rock samples after different soaking times to investigate the impact of hydration on shale mechanical properties and its failure mechanism.The results show that hydration weakens the shale cohesion,thereby significantly reducing its peak stress and elastic modulus.Moreover,as hydration time increases,the failure mode of the rock transitions from brittle to plastic.Meanwhile,there exists a critical point in the deterioration of shale mechanical strength under hydration:the post-deterioration mechanical strength is about 69.19% of that in dry conditions.The findings are of great significance for understanding the hydration-induced mechanical deterioration behavior of underground engineering rock masses and guiding stability evaluations for engineering projects.
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