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

Figure 10

The evolution of the effective stress in the surrounding rock at different times. (a) K = 1.15. (b) K = 1.25. (c) K = 1.5. (d) K = 1.75.

(a)

(b)

(c)

(d)