Abstract The peak explosion pressure acting on the borehole wall in decoupling charge blasting was investigated by employing analytical, numerical, and experimental approaches. The theoretical solution of the pressure increase ratio after collision between an air shock wave and an elastic wall was derived to analyse factors influencing the peak explosion pressure acting on the borehole wall. A numerical simulation of fluid–solid coupling using a dynamic finite element method was used to study the peak explosion pressure under the conditions of three types of rock, two common explosives, ten common radial decoupling coefficients, seven radial decoupling coefficients for experimental verification, and two axial decoupling coefficients. The results of the theoretical analysis and numerical simulation were used to obtain a calculation formula for the pressure increase ratio; this formula mitigates the shortage of the unreasonable value range and the uncertain value present in the previous methods. Further, an improved method for calculating the peak explosion pressure acting on the borehole wall in decoupling charge blasting was proposed by referencing an isentropic expansion and adiabatic expansion model for calculating the borehole pressure; the effect of the axial decoupling charge coefficients on the peak explosion pressure acting on the borehole wall was considered. Furthermore, the experiment results obtained by placing explosive cartridges in steel tubes to simulate decoupling charge blasting and the calculation results obtained using the improved method proposed in this paper show good agreement, thereby verifying the reliability and accuracy of the improved method. This research provides an improved method for determining the peak explosion pressure acting on the borehole wall as the key parameter of blasting design in contour blasting and a numerical simulation related to the blasting vibration response of non-fluid–solid coupling.

中文翻译：

---

一种计算解耦装药爆破井壁峰值爆炸压力的改进方法

摘要 采用解析、数值和实验方法研究了去耦装药爆破作用在钻孔壁上的峰值爆炸压力。推导了空气冲击波与弹性壁面碰撞后压力增加比的理论解，分析了影响作用在井壁上的峰值爆炸压力的因素。采用动态有限元法进行流固耦合数值模拟，研究了三种岩石、两种常用炸药、十种常用径向解耦系数、七种径向解耦系数条件下的峰值爆炸压力，用于实验验证，两个轴向解耦系数。通过理论分析和数值模拟的结果，得到了增压比的计算公式；该公式弥补了以往方法存在的取值范围不合理和不确定值的不足。进一步，参考等熵膨胀和绝热膨胀模型计算井壁压力，提出了一种改进的计算解耦装药爆破作用在井壁上的峰值爆炸压力的方法。考虑了轴向解耦装药系数对作用在钻孔壁上的峰值爆炸压力的影响。此外，将炸药筒放置在钢管中模拟解耦装药爆破的实验结果与本文提出的改进方法得到的计算结果具有较好的一致性，从而验证了改进方法的可靠性和准确性。该研究为确定作用在钻孔壁上的峰值爆炸压力作为轮廓爆破中爆破设计的关键参数以及与非流固耦合爆破振动响应相关的数值模拟提供了一种改进方法。