Multifield Coupling Mechanism of Unloading Deformation and Fracture of Composite Coal-Rock

Figure 7

Magnetic field intensity generated by coal loading and unloading at different times corresponding to the six time points ABCDEF in Figure 2. (a) t = 1.5 s, (b) t = 2.5 s, (c) t = 3.75 s, (d) t = 5.15 s, (e) t = 5.8 s, and (f) t = 7.5 s.

(a)

(b)

(c)

(d)

(e)

(f)