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

Figure 5

Deviatoric strain-stress curve of sandstone specimens under different confining pressure unloading rates. (a) Triaxial compression. (b) (v) = 0.002 MPa/s. (c) (v) = 0.02 MPa/s. (d) (v) = 0.2 MPa/s.

(a)

(b)

(c)

(d)