Presplit Blasting Technique in Treating Hard Overlying Strata: From Numerical Simulation to Field Practice

Figure 20

The evolution of the effective stress in the surrounding rock without split at different times. (a) T = 0.58 ms. (b) T = 1.0 ms. (c) T = 1.42 ms. (d) T = 2.0 ms. (e) T = 2.50 ms. (f) T = 3.30 ms.

(a)

(b)

(c)

(d)

(e)

(f)