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Abstract：
The area of permafrost worldwide accounts for approximately 20% to 25% of land area. In cold-climate regions of China, which are garnering international attention, the study of low-temperature and moisture effects on rock mass mechanical properties is of significant importance. China has a wide area of cold regions. This research can provide a foundation for China\'s exploration activities in such extreme environments. This paper examines the mechanical behavior of rock specimens subjected to various low temperatures and water contents through uniaxial compression tests. The analysis encompasses failure modes, stress-strain relationships, uniaxial compressive strength (UCS), and elastic modulus (EM) of these specimens. Findings reveal that at lower temperatures, the rock specimens\' fracture patterns transition from compressive shear failure to cleavage failure, reflecting a shift from a plastic-elastic-plastic to a plastic-elastic response. Specifically, saturated rocks exhibit a 40.8% decrease in UCS and an 11.4% reduction in EM compared to their dry counterparts. Additionally, in cold conditions, an increased water content in rocks primarily leads to vertical cracking. Under such conditions, saturated rocks show a 52.3% decline in UCS and a 15.2% reduction in EM, relative to their dry state.
摘要：
全球多年冻土面积约占土地面积的20％至25％。在中国的寒冷气候地区，引起了国际关注，研究低温和水分对岩体力学性质的影响具有重要意义。中国有广阔的寒冷地区。本研究为我国在此类极端环境下的勘探活动提供了基础。本文通过单轴压缩试验研究了岩石试样在各种低温和含水量下的力学行为。分析包括故障模式，应力-应变关系，单轴抗压强度（UCS），和弹性模量（EM）的这些样品。研究结果表明，在较低的温度下，岩石标本的断裂模式从压缩剪切破坏过渡到解理破坏，反映了从塑性-弹性-塑性到塑性-弹性响应的转变。具体来说,与干岩石相比，饱和岩石的UCS降低了40.8％，EM降低了11.4％。此外,在寒冷的条件下，岩石中含水量的增加主要导致垂直开裂。在这样的条件下,饱和岩石显示UCS下降52.3%，EM下降15.2%，相对于他们的干燥状态。
