Mechanical and Coal Burst Breeding Mechanism of Coal Samples under True Triaxial Loading and Unloading

Figure 3

The major principal stress-time and AE energy-time curves of coal samples. (a) Sample M (rate: 2.77 mm/min). (b) Sample N (rate: 6.12 mm/min). (c) Sample O (rate: 4.26 mm/min); (d) Sample P (data loss). (e) Sample Q (rate: 3.86 mm/min); (f) Sample R (rate: 4.78 mm/min).

(a)

(b)

(c)

(d)

(e)

(f)