| 1 | Match the balance marks carefully and complete by tapering the stitching past the drill hole in the usual way. | |
| 2 | Tunnels in rock are all dug by the method by drilling a small hole, packing explosive and dynamiting. | |
| 3 | Most darts are marked with notches for the dart site and drill hole for the point at which the dart terminates . | |
| 4 | Tunnel in hard rock may be excavated in whole section by using chiseling rock trolley to drill small holes. | |
| 5 | The paper summarized the technical key points of the excavation with the drilling and blasting method for the freezing thick gravel stratum section of the mine shaft. |
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