An application of the modified Holmberg–Persson approach for tunnel blasting design

• We use the modified Holmberg–Persson approach to design the full tunnel blast round.
• We make the detailed description of the modified Holmberg–Persson approach.
• Designing a cut pattern with the modified Holmberg–Persson approach is possible.
• We obtain the site specific limiting PPV values and the Holmberg–Persson constants.
• A new equation to calculate the crushed zone radius has been derived.

In this study, the applicability of the modified Holmberg–Persson approach for a tunnel blast design was investigated. For this purpose, firstly, a detailed description of the modified Holmberg–Persson approach was made. After that, data collection program for the statistical analysis of the ground vibration parameters induced by the tunnel blasting was presented and then the determination of the critical peak particle velocity level associated with the rock damage was described. Finally, site-specific limiting peak particle velocity values obtained by measuring the overbreak after blasting were given. The results of the field investigations were discussed and a new equation to calculate the crushed zone radius was derived. The studies have shown that Holmberg–Persson approach which was originally suggested for perimeter control design technique, can also be applied for a full blasting round to select the proper explosive-hole combinations.