Experimental Observations and Statistical Modeling of Crack Propagation Dynamics in Limestone by Acoustic Emission Analysis During Freezing and Thawing

The timing and location of microcracking events, their propagation coalescence to form macrocracks, development by tension, shearing or mixed modes are little known but essential understanding the fracture intact rock freezing thawing. aims present study investigate mechanisms transition macrocracking during repeated freeze-thaw, develop a statistical model crack that assesses distance angular relationship neighboring cracking events arranged in temporal order occurrence. Eight acoustic emission (AE) sensors mounted on 300 mm cubic block chalk captured three-dimensional locations occurrence 16 seasonal freeze-thaw cycles simulating an active layer above permafrost. AE occurred mostly thawing periods (45%) freeze-to-thaw transitions (37%) rather than (9%) thaw-to-freeze (8%), suggesting most (microcrack) were driven process ice segregation volumetric expansion. outcomes novel based two boundary conditions—inside-out outside-in cracking—were assessed Bayes’ theorem testing hypothesis inside-out mode was favored tensional activity, whereas supported events. In both situations, accounted for 54%–73% confidence level. microcrack can distinguish reasonably between cracks formed expansion segregation.