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In order to understand the correlation between coal structure and physical property of coal, samples with different coal structures were collected from the Late Permian period coal seams in the Laochang area, Yunnan Province, China. A set of experiments were carried out to quantitatively characterize the physical properties of coals with different coal structures using advanced and nondestructive low-field nuclear magnetic resonance (NMR) and X-ray computed tomography (X-CT). The experimental results gave us confidence to conclude that the evolution of the coal structures can be divided into five stages with stress increasing: the fractures closing stage, the microfractures development stage, the cracks development stage, the shear deformation stage, and the plastic deformation stage. Each stage corresponds to a different coal structure with unique physical characteristics. The undeformed coal is dominated …