Mechanical and microstructural properties of schist exposed to freeze-thaw cycles, dry-wet cycles, and alternating actions

• Liquid water is a critical factor in reducing the brittleness of schist under cyclic environmental actions. • The attenuation function model accurately predicts peak stress and elastic modulus degradation (R2 > 0.97). • Freeze-thaw cycles in water (FTW) cause the most severe deterioration, with the shortest half-life for strength (28 cycles) and wave velocity (208 cycles). • Damage variables for compressive strength and elastic modulus increase with cycle number, with FTW showing the highest damage after 40 cycles.