负温下模拟月壤三轴压缩试验与分析

Triaxial Compression Test and Analysis of Simulated Lunar Soil at Negative Temperature

为了确保未来月球基地建设的顺利进行,开展冻结模拟月壤力学特性的试验研究。在围压为0.8 MPa、1.6 MPa、2.4 MPa和温度为-15℃、-10℃、-5℃条件下进行三轴压缩试验,试验结果表明:冻结模拟月壤的偏应力-轴向应变曲线表现为应变硬化特性,曲线可分为压密阶段、弹性阶段、塑性阶段和破坏阶段;当温度一定时,随着围压增大,试样的弹性模量逐渐增大,泊松比逐渐减小;在负温条件下,温度对模拟月壤的内摩擦角影响不明显,黏聚力和弹性模量随着温度的降低而增大;在相同的温度和围压下,模拟月壤的E_(0)值比E_(0.5)值对围压的变化更敏感。

In order to ensure the smooth construction of the future lunar base,the experimental study on the mechanical properties of frozen lunar soil simulation was carried out.Triaxial compression tests were carried out under confining pressures of 0.8 MPa,1.6 MPa and 2.4 MPa and temperatures of-15℃,-10℃and-5℃.The results showed that the deviated stress-axial strain curves of the frozen lunar soil showed strain hardening characteristics,and the curves could be divided into compaction stage,elastic stage,plastic stage and failure stage.When the temperature is constant,the elastic modulus increases and poisson’s ratio decreases with the increase of confining pressure.Under the condition of negative temperature,the internal friction angle of the lunar soil was not significantly affected by temperature,and the cohesion and elastic modulus increased with the decrease of temperature.Under the same temperature and confining pressure,the value of E_(0) was more sensitive to confining pressure than that of E_(0.5).