为了研究注浆体在荷载作用下裂隙动态演化过程，以级配砂砾注浆试块为研究对象，利用 CT 扫描系统对其单轴压缩破坏过程进行阶段性扫描。通过图像重构技术实现注浆体试块内部裂隙结构空间可视化，定量表征裂隙数目和体积等结构特征参数；采用 Python 编程对 CT 切片的灰度值和分形维数进行计算，分析试块不同阶段的细观损伤程度。结果表明：整个压缩阶段，注浆体试块内部裂隙体积呈现缓慢上升−缓慢下降−缓慢上升−急速上升趋势，裂隙数目呈现先增大后减小的趋势；裂隙扩展遇到砂砾时，多为绕砾扩展，少数情况出现穿砾扩展，裂隙分叉扩展多发生在水泥基体与砂砾的界面处；按试块内部裂隙演化过程可将破坏分为4个阶段：初始缺陷扩张阶段、压密阶段、裂隙加速扩展阶段和裂隙贯通阶段；试块同一阶段同层切片的损伤变量与分形维数在数值上呈现一定的正相关性，与其裂隙体积演化趋势相似。研究成果可为深入研究注浆体失效过程及裂隙演化规律提供参考依据。To studythe fracture dynamic evolution process of grouting specimens under loadingconditions

the graded gravel grouting specimen was periodically scanned duringthe uniaxial compression damage process using a CT scanning system. Based onthe image reconstruction technique

the spatial visualization of the fracturestructure inside the test grouting specimen block is achieved

and thestructural characteristic parameters are characterized quantitatively such asthe number and volume of fractures. The gray value and fractal dimension of theCT slices are calculated using Python programming to analyze the mesoscaledamage extent at different loading stages of the grouting specimen. It is shownthat the specimen’s internal fracture volume shows a trend of slow rise

slowfall

slow rise

and rapid rise. The fracture number shows a trend ofincreasing firstly and then decreasing during the whole compression stage. Whenthe fracture expansion paths encounter gravel

most of the fractures expandaround the gravel location and few fractures expand through the gravel. Inaddition

the fracture bifurcation expansion mostly appears at the interfacebetween the cement matrix and gravel. The specimen damage process could bedivided into four stages in terms of the fracture evolution process inside thespecimen: initial defect expansion stage

internal crack compacting stage

fracture expansion stage

and fracture penetration stage. For the slice at thesame loading stage of the test specimen

it is found that the value of the damagevariable and fractal dimension shows a certain positive correlation

which issimilar to the trends of the fracture volume evolution. Theresearch results can provide a reference for the study of the failure processand fracture evolution law of the grouting body.