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

Figure 18

The evolution of the effective stress in the surrounding rock with the borehole spacing of 6 m at different times. (a) T = 2.7 ms. (b) T = 4.6 ms. (c) T = 8.6 ms.

(a)

(b)

(c)