Weather induced freeze-thaw cycles can cause significant alternation on soil volume and hence induce serviceability issues to earthen and structures facilities. However, the contribution of soil structure has rarely been considered in this process. In this research, a modified double-cell triaxial system is employed to accurately measure soil volume change under stress-controlled condition during freeze-thaw cycles. The device is adopted to investigate the volumetric behaviour of reconstituted and compacted sandy silt specimens under different confining pressures. The test results reveal that the change of freezing expansion slightly decreases with increasing number of freeze-thaw cycle because the dissipation of water is negligible. However, the thawing contraction decrease with freeze-thaw cycles. Thus, the total volume of soil tends to be stable when thawing contraction yields to be equal to freezing expansion. This trend is independent with preparation methods and confining pressure. Under 100 kPa of confining pressure, compacted specimen results in less plastic strain during freezing and thawing process compared with reconstituted specimen. A possible reason is that clay-formed aggregates enhance the soil skeleton, which is evidenced by MIP test result. Under 200 kPa confining pressure, two specimens using different preparation methods have almost identical volumetric behaviour which is attributed to the degradation of soil structure resulting from the increase of confining pressure.

天气引起的冻融循环会导致土壤体积发生显着变化，从而导致土方和结构设施的可用性问题。然而，在这个过程中很少考虑土壤结构的贡献。在这项研究中，采用改进的双池三轴系统来准确测量冻融循环期间应力控制条件下的土壤体积变化。采用该装置研究了不同围压下重组压实砂质粉砂试件的体积行为。试验结果表明，随着冻融循环次数的增加，由于水分的耗散可以忽略不计，冻胀的变化略有减小。然而，解冻收缩随着冻融循环而减小。因此，当解冻收缩产量等于冻结膨胀时，土壤的总体积趋于稳定。这种趋势与制备方法和围压无关。在100 kPa的围压下，压实试样在冻融过程中的塑性应变比重组试样要小。一个可能的原因是粘土形成的聚集体增强了土壤骨架，MIP 测试结果证明了这一点。在200 kPa围压下，两种不同制备方法的试件具有几乎相同的体积行为，这是由于围压增加导致土壤结构退化。在100 kPa的围压下，压实试样在冻融过程中的塑性应变比重组试样要小。一个可能的原因是粘土形成的聚集体增强了土壤骨架，MIP 测试结果证明了这一点。在200 kPa围压下，两种不同制备方法的试件具有几乎相同的体积行为，这是由于围压增加导致土壤结构退化。在100 kPa的围压下，压实试样在冻融过程中的塑性应变比重组试样要小。一个可能的原因是粘土形成的聚集体增强了土壤骨架，MIP 测试结果证明了这一点。在200 kPa围压下，两种不同制备方法的试件具有几乎相同的体积行为，这是由于围压增加导致土壤结构退化。