Digital image correlation (DIC) and particle image velocity (PIV) are highly effective non-contact methods to accurately measure full-field deformations in transparent soil model testing (TSMT). The nature of transparent soils combined with the rapid development of three-dimensional (3D) DIC/PIV techniques means that the acquisition of the full internal 3D deformations is now technically feasible. However, current approaches focus on two-dimensional (2D) in-plane displacements and typically ignore out-of-plane displacements. This paper presents an approach of combining 3D-DIC with optical slicing to observe 3D movements of transparent soil using custom MATLAB programming. A rigid body motion (RBM) test of a transparent soil sample is first conducted to estimate the accuracy of the proposed algorithm. A vertically loaded circular footing test is subsequently performed as a proof of concept; multiple-slice images of the soil are captured using a new experimental apparatus and processed by the 3D-DIC algorithm, and the resultant 3D displacements of all slices are reconstructed to visualize the soil deformations in 3D space. The findings confirm that the proposed 3D-DIC algorithm is accurate and the optical slicing with supplementary spatial reconstruction method enables visualization of transparent soil in 3D space, which can be used in future TSMT.

数字图像相关 (DIC) 和粒子图像速度 (PIV) 是精确测量透明土模型测试 (TSMT) 中全场变形的高效非接触方法。透明土壤的性质与三维 (3D) DIC/PIV 技术的快速发展相结合，意味着获取完整的内部 3D 变形现在在技术上是可行的。然而，当前的方法关注二维（2D）面内位移，并且通常忽略面外位移。本文提出了一种将 3D-DIC 与光学切片相结合的方法，以使用自定义 MATLAB 编程来观察透明土壤的 3D 运动。首先对透明土壤样本进行刚体运动（RBM）测试，以评估所提出算法的准确性。随后进行垂直加载的圆形基础测试作为概念验证；使用新的实验装置捕获土壤的多切片图像，并通过 3D-DIC 算法进行处理，并重建所有切片的 3D 位移，以可视化 3D 空间中的土壤变形。研究结果证实，所提出的 3D-DIC 算法是准确的，并且光学切片和补充空间重建方法可以实现 3D 空间中透明土壤的可视化，可用于未来的 TSMT。