Effects of Constant Amplitude Cyclic Loading on the Nonuniform Deformation of Sandstone Specimens

Figure 8

Evolution curves of S_w under the same stress: (a) loading or unloading to 15 MPa; (b) loading or unloading to 20 MPa; (c) loading or unloading to 25 MPa; (d) PPL or BPU.

(a)

(b)

(c)

(d)