Abstract: This experimental study examines the shear behaviors of sandstone and its performance in different water conditions under low temperature cycling environment. The results show that after a sandstone sample experienced low temperature cycles, its internal friction angle and cohesion are reduced to varying degrees and the reduction amplitude increase with the water content. And the roughness coefficient of its shear failure surface increases with saturation coefficient. For water-enriched sandstone, we find that its shear failure mode is significantly affected by low temperature cycling, and the increase in its failure surface roughness coefficient with the cycling number follows the power law. And the damage factor of internal friction angle and cohesion with the increasing roughness coefficient take an exponential form. This study lays a basis for further study of the shear failure model of sandstone in low temperature environment and its shear behaviors through inversion analysis from the original state of damaged sandstone in cold regions.

Key words: low temperature cycle, sandstone, internal friction angle, cohesion, roughness coefficient