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随着我国高寒区沙漠化问题的日益严重,由此产生的地表风沙堆积对多年冻土影响的范围和强度越来越大,但目前风沙堆积对多年冻土温度的影响过程及机理仍不明确,特别是缺少室内模型试验方面的研究.通过室内试验模拟了不同厚度的积沙对多年冻土温度的影响.结果表明:除试验箱气温为正负温过渡阶段外,当试验箱气温为负温时期,积沙冻土的中上层温度比无积沙冻土高,且沙层越厚温度越高,但均为负温,整个土层仍对应冻结状态;当试验箱气温为正温时期,积沙冻土的中上层温度比无积沙冻土低,且沙层越厚温度越低,而正温阶段对应冻土融化时期,积沙的降温作用可延缓冻土的融化.在3个冻融循环周期内,积沙冻土的底面平均温度均比无积沙冻土低,且沙层越厚,冻土底面温度波幅越小.
With the worsening of desertification in the alpine region of China, the scope and intensity of surface aeolian sand accumulation affecting permafrost are more and more large. However, the process and mechanism of the impact of aeolian sand accumulation on permafrost temperature remain unclear. Especially the lack of research on indoor model test.The indoor temperature and temperature of permafrost with different thicknesses are simulated by indoor test.The results show that when the temperature of test chamber is minus temperature and the temperature of test chamber is minus temperature During the period, the temperature of the upper and middle layer of the frozen soil was higher than that of the non-covered frozen soil, and the thicker the layer, the higher the temperature was, but both were negative temperature and the entire soil layer still corresponded to the frozen state. When the chamber temperature was positive, The temperature of upper and middle layer of frozen soil is lower than that of non-sedimentary frozen soil, and the thicker the layer of sand, the lower the temperature, while the positive temperature phase corresponds to the thawing period of frozen soil, During the freeze-thaw cycles, the average temperature of the bottom of the frozen soil is lower than that of the non-sedimentary frozen soil, and the thicker the sand, the smaller the temperature fluctuation of the bottom of the frozen soil.