冻融循环条件下人工冻土力学特性试验研究

Mechanics characteristic test of artificial frozen soil under freeze-thaw cycles condition

通过两淮地区深部人工冻土在不同含水率和温度(-5℃、-10℃、-15℃等3温度水平)下进行冻融循环单轴瞬时强度试验。结果表明:在温度-5℃条件下,不同含水率的冻土随着冻融循环次数的增加,瞬时强度先减小后增大。当试验温度为-10℃时,随着冻融作用次数的增加,强度先增加后减小,但变化幅度不大。当试验温度为-15℃时,冻融作用对人工冻土的强度影响不显著。在试验温度范围内,冻融循环使人工冻土强度变化范围为0.16~1.32 MPa。试验结果可以对深部矿井冻结法设计和施工提供科学指导。

This paper introduces the uniaxial unconfined compressive strength test of artificial frozen soil from huaibei area under different moisture contents and freezing temperatures（-5℃,-10℃,-15℃）freeze-thaw cycles.Results show that the freezing temperature（-5℃）,under the condition of high moisture content of different freezing soil with the increase of freeze-thaw cycles,the unconfined compressive strength increases with the decrease of the first.When high freezing temperature（-10℃）,with the increase of number of freeze-thaw action,instantaneous strength increases first and then decreases,but the change is very small.When the freezing temperature is -15℃,freezing and thawing effect of artificial frozen soil uniaxial compressive strength of the effect is not significant.In the range of test temperature,the variation range of the freeze-thaw is 0.16-1.32 MPa.The experimental results can provide scientific guidance for the design and construction of deep mine freezing method.