Damage mechanical properties of sandstone under different freeze-thaw conditions

In order to explore the freeze-thaw damage and mechanical properties of sandstone under different freeze-thaw conditions, sandstone undergone different freeze-thaw cycles and cycle times is selected for uniaxial compression tests and acoustic emission monitoring tests. The damage evolution equations of sandstone are established, with the test results and the statistical damage theory. The results show that: Both freeze-thaw cycle and cycle times affect the freeze-thaw damage of sandstone. The strength and elastic modulus of sandstone decrease exponentially and linearly with the increase of freeze-thaw cycle and cycle times respectively. The cumulative ringing counts are consistent with the stress-strain curves. The cumulative ringing count in the compaction stage and linear elastic stage is very small. The cumulative ringing count in the plastic deformation stage gradually increases, and the growth rate keeps rising. The cumulative ringing count in the post peak damage stage increases dramatically. The longer the freeze-thaw cycle and the more cycle times, the smaller the cumulative ringing count of sandstone. The freeze-thaw damage variable determines the initial value of the total damage variable under freeze-thaw and load. The damage evolution curve can be divided into three stages: in the initial stage damage rarely increase, in the development stage damage increases gradually, and the growth rate is getting higher, and in the accelerated stage damage increases dramatically and causes macro damage of sandstone. © 2024 China University of Mining and Technology. All rights reserved.