Microscopic Investigation of Rate Dependence on Three-Point Notched-Tip Bending Sandstone

Figure 6

Typical variation in load and AE count rate with time for TPB tests under different loading rates: (a) 0.6 mm/min, (b) 1.0 mm/min, (c) 1.4 mm/min, (d) 1.8 mm/min, and (e) 3.0 mm/min. I, II, and III represent elastic stage, damage stage, and postpeak stage, respectively.

(a)

(b)

(c)

(d)

(e)