Qingdao University of Technology, Qingdao, 266033, Shandong, China.
Shandong University, Qingdao, 266237, Shandong, China.
Sci Rep. 2021 Nov 30;11(1):23177. doi: 10.1038/s41598-021-02662-9.
This paper presents an experimental investigation on the effect of freeze-thaw cycling on expansive soil slopes with different initial moisture contents. Clay soil from Weifang, China, was remolded and selected to build the expansive soil slope for the indoor slope model tests. A total of five freeze-thaw cycles were applied to the three expansive soil slopes with different moisture contents ranging from 20 to 40%. Variations of the crack developments, displacements, soil pressures and moisture contents of the expansive soil slope with different initial moisture contents during the freeze-thaw cycling were reported and discussed. The results indicate that higher moisture contents can slow the development of cracks and that the soil pressure increases with decreasing temperature. The soil pressure of slope decreases after freeze-thaw cycle, and the change amplitude of soil pressure after freeze-thaw is proportional to water content. The slopes with a moisture content of 20% and 30% shrinks during freezing and expands during thawing, which was named ES-FSTE Model, while the slope with a 40% moisture content shows the opposite behavior. During freeze-thaw cycles, moisture migrates to slope surface. As initial moisture contents increase, the soil heat transfer rate and bearing capacity decreases after five freeze-thaw cycling.
本文对不同初始含水率的冻融循环对膨胀土边坡的影响进行了试验研究。采用取自中国潍坊的粘土重塑并选取来建造用于室内边坡模型试验的膨胀土边坡。对三个初始含水率分别为 20%、30%和 40%的膨胀土边坡进行了总计五次的冻融循环。报告和讨论了不同初始含水率的膨胀土边坡在冻融循环过程中裂缝发展、位移、土压力和含水率的变化。结果表明，较高的含水率可以减缓裂缝的发展，土压力随温度的降低而增大。冻融循环后土压力减小，且土压力在冻融后的变化幅度与含水率成正比。含水率为 20%和 30%的边坡在冻结时收缩，在融化时膨胀，这种现象被命名为 ES-FSTE 模型，而含水率为 40%的边坡则表现出相反的行为。在冻融循环过程中，水分向边坡表面迁移。随着初始含水率的增加，经过五次冻融循环后，土壤的热传递速率和承载力降低。
