According to the hard wall-rock characteristics of Zhangxin Coal Mine Xinfeng Shaft and its drillability and blastability, appropriate cutting mode is adopted.

How to ensure the existing tunnel s safety and the train normal running while the electric railway multiple line tunnel was blast boring? By study and practice,the paper gives an answer through stepped digging method,underholing style,holes scatter and the structure of the hole and detonation technology.

However, the progressive spiral cutting has merits of few drilling, smaller charging and better blasting effectiveness.

Combining the specific engineering practice,this paper discussed the theoretic and practical bases of reasonable lying of the cuttings hole toward characteristics of the big cross-section sap tunneling demolition,and calculated the reference quantity of explosive in single hole under condition of the mild-rigidity rocks.

By using the LS-DYNA 3D nonlinear dynamic finite element software,the elasticity calculation model was established to analyze the generation and transmission of stress under explosive charge in 4 typical cutting patterns,those used in shaft excavation by one-step blasting were optimized and compared by numerical simulation to select the optimizing cutting patterns.

In this paper, the author combined the experience of tunnelling construction bystraight-in hole cutting blasting within 30 years in the country with the theory and practice in the blasting wor of Sweden, U.