Research Progress of Three-Dimensional Reconstruction Method Based on Microstructure of Rock

As a typical porous medium, the mechanical behavior of rock under macroscopic loading often relies on its microstructural characteristics. To provide quantitative analysis of the macroscopic mechanical behavior of rock, studying the micro-pore structure of rock is important. By systematically investigating the visualization and three-dimensional reconstruction techniques of rock microstructures, this paper summarizes the research progress of rock structure characterization methods from two aspects: image-based analysis and numerical reconstruction. Based on the requirements of rock samples, the impact of the testing process on samples, and the accuracy of characterizing the microstructures, we assess the advantages and limitations of serial section electron microscopy, Focused Ion Beam-Dual Beam Scanning Electron Microscopy, X-ray computed tomography and nuclear magnetic resonance imaging in the research of rock microstructures. We point out that although joint measurement with all methods can obtain smaller and wider scale range in the accuracy of rock characterization, there are still many problems in practical operation and scale splicing. These issues include high cost, difficulties in matching boundary scales, and inconsistent image ranges. Therefore, we propose that developing the three-dimensional reconstruction method for rocks that combines image and numerical algorithms can not only reflect the microscopic structural characteristics of rocks, but also ensure the accuracy of the overall characterization of rocks. Additionally, it can improve characterization efficiency and reduce characterization costs. This approach is a significant direction for the development of rock modeling and computational simulation methods.