Mechanical and Acoustic Emission Characteristics of Sandstone through Triaxial Unloading Test after Cyclic Freezing-Thawing Treatment

Figure 7

Representative SEM images of sandstone morphologies in microscale: (a) before freezing-thawing treatment; (b) after 40 freezing-thawing cycles; (c) after triaxial unloading test with typical intercrystalline crack; (d) after triaxial unloading test with typical transcrystalline crack; (e) after triaxial unloading test with typical intracrystalline crack.

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