For building demolition and tunneling, many shock tubes must be simultaneously initiated by a detonator. Bunches of shock tubes can be initiated by bunch blocks. The initiation reliability of shock tubes depends primarily upon bunch block design.
Understanding the structural explosion shock mechanisms of bunch blocks is very important in designing bunch blocks without consumption of many shock tubes in experiments.
Choe Yong Chol, a researcher at the Faculty of Mining Engineering, investigated the structural influence of frontal bunch blocks on the initiation reliabilities of bunches of shock tubes by a detonator experimentally and numerically.
The thicker and stronger bunch block bodies and the smaller the standoff distance between detonators and bunches of shock tubes were, the more the experimentally obtained initiation rates increased. And the pressure peaks of explosion shock obtained from numerical simulations increased with increase in the thickness of bunch block bodies and decrease in the standoff distance. The numerically obtained pressure peaks were in good relation with the initiation rate obtained from the experiments.
The results can be employed for evaluating initiation reliability and designing bunch blocks when simultaneous bunch-series initiation of many shock tubes by bunch blocks is needed.
For more information, please refer to his paper “Structural Influence of Frontal Bunch Blocks on the Initiation Reliability of Bunches of Shock Tubes” in “Proceedings of KUTIC-2025”.