黏土的触变性是指黏土受扰动后强度降低，静置之后强度逐渐恢复的现象，这种特殊的力学性质对工程建筑地基的承载力和稳定性有较为显著的影响。为了研究湛江组结构性黏土的触变特性及其微观结构演化特征，通过对不同初始含水率的重塑湛江组结构性黏土，采用无侧限抗压强度试验、扫描电镜（scanning electron microscopy, SEM）试验和核磁共振（nuclear magnetic resonance, NMR）试验，开展不同养护龄期下的试验分析。研究表明，湛江组结构性黏土的触变强度比率（A_t）随养护龄期的增长而增大，具体可分为3个阶段：触变强度比率迅速增大（触变性强）、增长速率减缓（触变性减弱）及趋于稳定（触变性逐渐消失）。土体在触变过程中，土颗粒之间的连接越来越牢固稳定，土颗粒骨架间的孔隙也随之定向排列有序性不断增强，孔隙形态趋于规则，土体整体微观结构从松散的絮凝结构向蜂窝—紧密絮凝状结构演化，越来越均质紧密。通过对触变强度比率和基于SEM图像提取的微观结构参数进行灰色关联分析可知：分形维数、概率熵和扁圆度与触变强度比率均具有明显的相关性，概率熵与土体的触变性强度比率相关性最高、其次为分形维数、最后是扁圆度，因此，应首选概率熵表征土体触变性变化规律，次选分形维数、扁圆度。

Thixotropy in clay, characterized by a reversible decrease in viscosity upon disturbance followed by gradual recovery, significantly influences the bearing capacity and stability of foundations in engineering structures. This study investigates the thixotropic properties and microstructural evolution of the Zhanjiang Formation structural clay. Analyses were conducted using unconfined compressive strength tests, SEM (scanning electron microscopy), and NMR (nuclear magnetic resonance), focusing on samples with varying initial moisture contents and curing ages. Results indicate that the thixotropic strength ratio (A_t) of the Zhanjiang Formation clay increases with curing age, characterized by three distinct phases: rapid increase indicating strong thixotropy, a slower growth rate suggesting weak thixotropy, and eventual stabilization where thixotropy diminishes. Microstructural observations reveal that the soil's particle bonds strengthen over time, and pore alignment becomes more orderly, evolving from a loosely flocculated structure to a more homogeneous and compact honeycomb-like configuration. Furthermore, through gray relational analysis of the microstructural parameters extracted from SEM images and thixotropic intensity ratio, it can be concluded that: fractal dimension, probability entropy, and flatness, with probability entropy showing the highest correlation. This suggests that probability entropy is most indicative of thixotropic behavior, followed by fractal dimension and flatness.