Microscopic Characteristics of Fractured Sandstone after Cyclic Freezing-Thawing and Triaxial Unloading Tests

Table 1

Mechanical properties of sandstones under unloading tests after various freezing-thawing cycles.

Number of freezing-thawing cycles	Peak strength (MPa)	Decreasing rate of damage dilatancy stress (%)	Damage dilatancy stress (MPa)	Decreasing rate of peak strength (%)
0	101.35	—	95.66	—
20	90.54	10.7	89.99	5.9
40	88.42	12.8	85.78	10.3
60	83.59	17.5	80.48	15.9
80	69.85	31.1	63.14	34.0