Influence of Confining Pressure Unloading Rate on the Strength Characteristics and Fracture Process of Granite Using Lab Tests

Table 3

Strength parameters of granite samples under different unloading confining pressure rates.

Confining pressure unloading rate (MPa/s)	Cohesion c (MPa)	Internal friction φ (°)
0.002	35.86	44.37
0.02	28.02	47.89
0.2	22.32	51.80