Quantitative Analysis of Mesoscopic Damage and Crack Evolution in Bedded Shales Based on Real‐Time CT Imaging

As energy demand grows, understanding shale's mechanical behavior is vital for efficient gas extraction. This study uses real‐time CT imaging to investigate mesoscopic damage evolution in shale under varying uniaxial loading rates. Through 3D reconstruction and image processing, we visualized and quantified void development. Real‐time strain monitoring provided insights into macroscopic deformation. A new damage model was proposed, linking damage variables to strain via a power‐law relationship. Results show mesoscopic damage initially decreases, stabilizes, then increases rapidly due to initial void compression and crack propagation. Pyrite distribution was identified as a key factor in crack initiation and growth. Cracks typically start near pyrite and follow its spatial pattern. The proposed model was validated against experimental data, demonstrating its reliability in capturing shale's damage evolution.