Application of Presplitting Blasting Technology in Surrounding Rock Control of Gob-Side Entry Retaining with Hard Roof: A Case Study

Figure 8

Test of roof cutting effect of presplitting blasting based on borehole peeping method. (a) Peeping results of typical deep hole presplitting blasting. (b) Peeping results of shallow hole blasting. (c) Symmetric fracture formation in a typical hole.

(a)

(b)

(c)