AI super-resolution reconstruction of nano-CT digital coal-rock
ZHANG Liao1, 2, LIU Yintong2, MAO Tingting1, 2, CHENG Jianchao1, 2, HOU Mengdong2, ZHOU Shenghao1, 2, LI Juan2, YAO Jinyue2, XUE Dongjie1, 2, 3?
(1. State Key Laboratory for Tunnel Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China; 2. School of Mechanics and Civil Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China;
3. State Key Laboratory of Intelligent Coal Mining and Strata Control, China Coal Technology and Engineering Group, Beijing 100013, China)
Abstract：Nano-scale coal-rock CT imaging offers the advantages of high resolution and three-dimensional structural reconstruction; however, its acquisition is expensive and its axial resolution is limited, which compromises digital core modeling and seepage simulation. To enhance axial resolution while preserving the true topological structure, this study proposes a generative adversarial network-based super-resolution reconstruction method, termed SRGAN-CT. The proposed method integrates residual blocks and a perceptual loss, and develops a specialized discriminator to strengthen the discrimination of structural details. In addition, a transverse-slice mapping strategy is adopted to construct the training dataset, and orthogonal experiments are conducted to evaluate the robustness and generalization performance of the model. The results show that SRGAN-CT effectively preserves both fine details and topological structures of nano-CT images under multiple upsampling factors and random perturbations, outperforming conventional super-resolution methods in terms of structural-metric deviations and topological errors. Overall, this study verifies the high-fidelity reconstruction capability of SRGAN-CT for 3D topological and geometric information, providing a new technical pathway for efficiently obtaining high-resolution digital cores.
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2026, Vol. 45 
