This study evaluates the effects of post-compaction wetting–drying (WD) process, freeze–thaw (FT) cycles and cement content (CC) on the microstructure, volumetric strain (ε_v), soil–water characteristic curve (SWCC), resilient modulus (M_R), unconfined compressive strength (q_u), and reloading modulus (E_1%) and axial stress (S_u1%) at 1% strain level of a cement-stabilized expansive soil. The specimens compacted with different CC (i.e. 0%, 2%, 4% and 6%) were subjected to different number of FT cycles (i.e. N_FT = 0, 1, 3 and 10). They were then dried or wetted to different moisture contents before the determination of the (i) SWCC using filter paper method, (ii) M_R from cyclic triaxial tests, and (iii) q_u, E_1%, and S_u1% from unconfined compression tests. The microstructural changes in the test specimens were determined using mercury intrusion porosimetry and scanning electron microscope tests. Experimental results reveal that cement stabilization and cracks induced during FT cycles cause a significant reduction in the specimen’s water retention capacity and the scale of volumetric strain upon moisture content fluctuation. The M_R, q_u, E_1% and S_u1% typically decrease with N_FT but increase with CC. However, their variation with moisture content changes is less significant after stabilization or FT cycles. Performance of several empirical models for predicting the M_R, q_u, E_1% or S_u1% was examined. Similar trends in behavior were found for M_R-q_u, M_R-E_1% and M_R-S_u1% relationships for the specimens tested with different CC, N_FT and water content. A simple hyperbolic model proposed in this study for predicting these relationships is validated. The studies presented in this paper are helpful for the design and analysis of stabilized expansive soils used as pavement subgrade considering the influence of complex environmental factors.

本研究评估后压实干湿（WD）过程中，冻融（FT）循环并在微观结构水泥含量（CC），体积应变的影响（ε _v），土-水特征曲线（SWCC），水泥稳定膨胀土在1％应变水平下的弹性模量（M _R），无侧限抗压强度（q _u），再加载模量（E _1％）和轴向应力（S _u1％）。用不同CC（即0％，2％，4％和6％）压实的样品经受不同数量的FT循环（即N _FT） = 0、1、3和10）。然后将它们干燥，或使用滤纸方法润湿以不同水分含量的（I）SWCC的判定之前，（ⅱ）中号_ř从循环三轴测试，和（iii）q _ù，ë _1％ ，和小号_U1％从无限制压缩测试。使用水银压入孔隙率法和扫描电子显微镜测试确定试样的微观结构变化。实验结果表明，水泥固结和在FT循环中引起的裂纹会导致试样的保水能力和水分含量波动时体积应变的明显降低。的中号_[R ，q_u，E _1％和S _u1％通常随着N _FT减小而随着CC增大。但是，在稳定或FT循环后，它们随水分含量变化的变化不太明显。检验了几种经验模型预测M _R，q _u，E _1％或S _{u1％的性能}。对于M _R - q _u，M _R - E _1％和M _R - S _u1％，也发现了类似的行为趋势。不同的CC，N _FT和水含量测试的样品之间的关系。验证了本研究中提出的用于预测这些关系的简单双曲模型。考虑到复杂的环境因素的影响，本文的研究有助于设计和分析用作路面路基的稳定膨胀土。