基于分形理论的海相固化土强度劣化分析

为了对海相固化土的劣化机理进行更深入的研究，采用Python+OpenCV图像处理软件对不同固化类型、不同侵蚀时间的海相固化土扫描电子显微镜(scanning electron microscope，SEM) 像进行处理和数据提取，在考虑图片亮度差异影响的基础上，引入分形理论定量分析固化土微观颗粒的变化规律，同时结合无侧限抗压强度试验结果，建立了海相固化土微观颗粒结构变化与宏观力学性能之间的关系。研究结果表明:(1)不同SEM图像由于亮度的差异会对研究结果产生影响，在进行二值化处理时可通过控制其整体像素量的方法减小误差；(2)受海水侵蚀的固化土其微观颗粒变化规律具有分形特点，对于水泥固化土(CS)和掺激发剂的钢渣粉+水泥固化土(A-SSP-CS)随着侵蚀时间的延长，其微观颗粒分形维数逐渐降低，而对于钢渣粉+水泥固化土(SSP-CS)其微观颗粒分形维数则随着侵蚀时间的延长而逐渐增大；(3)对于CS和A-SSP-CS其无侧限抗压强度(unconfined compression strength，UCS)会随着海水侵蚀时间的延长而逐渐降低，其微观颗粒分形维数也在逐渐降低，对于SSP-CS其UCS会随着海水侵蚀时间的延长而逐渐增强，其颗粒分形维数也逐渐增大。

Analysis of strength deterioration of marine solidified soil based on fractal theory

In order to conduct an in-depth study on the deterioration mechanism of marine solidified soil, Python+OpenCV image processing software is used to process and extract data from SEM images of marine solidified soil with different curing types and erosion time. On the basis of considering the influence of the difference in picture brightness, the fractal theory is introduced to quantitatively analyze the variation of microscopic particles of solidified soil. At the same time, combined with the test results of unconfined compressive strength, the relationship between the microscopic particle structure change of marine solidified soil and the macroscopic mechanical properties is established. The results show that: (1) the difference of brightness of different SEM images will have an impact on the results of the study. In the binarization process, the error can be reduced by controlling the whole amount of pixel (2) the microscopic particle variation of solidified soil eroded by seawater has fractal characteristics. For cement solidified soil (CS) and steel slag powder + cement cured soil (A-SSP-CS) mixed with activating agent, the fractal dimension of microscopic particles decreases gradually with the extension of erosion time, while the fractal dimension of microscopic particles increases with the extension of erosion time for steel slag powder + cement solidified soil (SSP-CS). (3) for CS and A-SSP-CS, the unconfined compressive strength (UCS) decreases gradually with the extension of seawater erosion time, and the fractal dimension of microscopic particles decreases gradually. For SSP-CS, its UCS will gradually increase with the extension of seawater erosion time, and the fractal dimension of particles will also increase gradually.