Research Article

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

Figure 19

The evolution of the effective stress in the surrounding rock with the borehole spacing of 8 m at different times. (a) T = 3.5 ms. (b) T = 5.5 ms. (c) T = 7.0 ms.
(a)
(b)
(c)