Experimental Study on Mechanical Properties of Freeze-Thaw Damaged Red Sandstone under Combined Dynamic and Static Loading

Figure 4

Scanning electron microscope images of rock samples before and after freeze-thaw (×300). (a) 0 cycles, (b) 10 cycles, (c) 20 cycles, and (d) 30 cycles.

(a)

(b)

(c)

(d)