Science and Technology of Energetic Materials

Vol.68, No.6 (2007)

Research paper

A study on smooth blasting technique using detonating cords
Fumihiko Sumiya and Yukio Kato


Smooth blasting technique is applied for tunnel excavation to obtain a good quality perimeter. In general, the explosives with small charge diameter are used and loaded into borehole by decoupling. However, smooth blasting technique often causes problem related to detonation failure in explosive charge. This phenomenon is well known as the channel effect. We have chosen some kinds of detonating cords as the explosives with good detonation propagation, and investigated its application for smooth blasting. Approach for its application was proceeded by three steps. At the first step, the breakage of steel pipes was investigated in laboratory scale when the bunch of detonating cords was detonated. At the next step, mini-blasting tests on small square face were conducted. And at the final step, the bunches of detonating cords were applied for the contour holes of an actual tunneling blast. Hence, it is concluded that the relationships between the total core load of detonating cords and the hole spacing have an accordance with some equation.

> Full text (Open access*)


Detonating cord, Smooth blasting, Decoupled, Overbreak, Field test.

© Copyright 1999-2017 Japan Explosives Society. All right reserved.