This paper proposes a parameter calculation method for the mixed initiation circuit with both nonel detonators (NDs) and electronic detonators (EDs) to increase the detonator delay for reducing the blast-induced vibration in tunnel blasting and to ensure safe circuit operation. The circuit involves the outside-hole delay for increasing the delay numbers under the premise of safe circuit operation. The time calculation and vibration-reduction effects of the circuit were quantitatively determined through mathematical modeling and field experimental studies. A calculation model of mixed detonator groups was established based on three constraint conditions: no delay irregularly, no misfire, and an increased delay number. The main parameters obtained were the initiation sequence of the EDs, the delay number of the NDs and the time interval of the EDs inside the blastholes. The factor considered in the mathematical modeling was the delay error of the NDs. The calculation results agreed well with experimental results, the latter confirming that the mixed initiation circuit was feasible and safe when using a 90 ms delay outside the blasthole. In addition, the delay numbers of the mixed-detonator group were increased by 40% relative to those of NDs. Compared with conventional blasting that reduces the advance per round, blasting with the mixed initiation circuit using an outside-hole delay produced 82.3% less blast-induced vibration. It was also found that the blasting cost could be reduced by 54.3% compared with that of using EDs only. Overall, the mixed initiation method had a positive effect on tunnel controlled-blasting. The research methods and results are expected to be useful in guiding related engineering efforts.

本文提出了一种用于非爆轰雷管和电子雷管的混合起爆电路的参数计算方法，以增加雷管延迟，以减少隧道爆破中爆破引起的振动，并确保电路的安全运行。在安全电路操作的前提下，电路会涉及外孔延迟，以增加延迟数。通过数学建模和现场实验研究，定量确定了电路的时间计算和减振效果。基于三个约束条件，建立了混合雷管群的计算模型：无规律性无延迟，不发火，延迟数增加。获得的主要参数是ED的起始顺序，爆破孔内ND的延迟数和ED的时间间隔。数学建模中考虑的因素是ND的延迟误差。计算结果与实验结果吻合得很好，后者证实了在爆破孔外使用90 ms延迟时，混合启动电路是可行和安全的。此外，与雷管相比，混合雷管组的延迟数增加了40％。与传统的爆破相比，这种爆破降低了每轮的推进速度，而使用外孔延迟的混合起爆电路进行爆破，则爆破引起的振动降低了82.3％。还发现与仅使用ED相比，喷砂成本可以降低54.3％。总体而言，混合起爆方法对隧道控制爆破具有积极作用。