Analysis and Application on Controlling Thick Hard Roof Caving with Deep-Hole Position Presplitting Blasting

<div>Evolution law of blasting-induced cracks (A: crushed zone; B: initial crack zone; C: the secondary fracturing length and interconnection zone induced by detonation gas). (a) 149.8 <i>μ</i>s, (b) 349.3 <i>μ</i>s, (c) 569.6 <i>μ</i>s, and (d) 749.6 <i>μ</i>s.</div>

Advances in Civil Engineering

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Figure 12

Figure 12: Analysis and Application on Controlling Thick Hard Roof Caving with Deep-Hole Position Presplitting Blasting 