PURPOSE: A center cut aligning structure for a smooth blasting tunnels is provided to reduce the cost required for manufacturing a special hole perforating apparatus and to effectively excavate a tunnel by perforating a gunpowder non-charging hole formed in the center cut using a conventional jumbo drill. CONSTITUTION: A center cut(2) is formed at a center of a free surface of a tunnel. The first expansion hole, the second expansion hole, left and right sidewall holes, an apex hole, and a bottom hole are formed around the center cut(2). A plurality of gunpowder charging holes are formed in the above holes with a predetermined interval. Gunpowder non-charging holes and gunpowder charging holes are formed in the center cut(2). Three gunpowder non-charging holes(21a,21b,21c) are vertically formed at a center of the center cut(2). Two first-blasting gunpowder charging holes(22) are formed at both sides of the gunpowder non-charging hole(21b). Four second-blasting gunpowder charging holes(23) are aligned at both sides of the gunpowder non-charging holes(21a,21c).
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