In rock blasting, the effect that stress wave superposition between boreholes has on rock fragmentation remains controversial. Here, we experimentally study the stress wave superposition effect between two adjacent boreholes by combining the model experiment method and the high-speed digital image correlation experimental system. Numerical simulations based on the continuous-discontinuous element method are also used to analyze the crack initiation mechanism between two adjacent boreholes. The model experiment results show that, in the stress wave superposition area between boreholes, the stress component in the direction of the connection line of the two boreholes is mainly compressive, while that in the direction perpendicular to the connection line is mainly tensile. Superposition of the blasting stress waves between the boreholes strengthens both stress components, but the strengthening effect on the stress component in the direction perpendicular to the connection line (mainly tensile) is significantly less than that in the direction of the connection line (mainly compressive). Moreover, these stress enhancements are not sufficient to induce crack initiation in the stress wave superposition area between boreholes. Numerical simulation analysis further shows that crack initiation in the stress wave superposition area has relatively stringent requirements on the explosive parameters, rock properties and borehole spacing, which are difficult to observe in engineering practice and model experiments.

在爆破中，井眼之间的应力波叠加对碎石的影响仍存在争议。在这里，我们结合模型实验方法和高速数字图像相关实验系统，对两个相邻井眼之间的应力波叠加效应进行了实验研究。基于连续-不连续元法的数值模拟也用于分析两个相邻钻孔之间的裂纹萌生机理。模型实验结果表明，在井眼之间的应力波叠加区域中，两个井眼的连接线方向上的应力分量主要是压缩应力，而垂直于井线的方向上的应力分量主要是拉伸应力。钻孔之间的爆破应力波叠加会增强两个应力分量，但是在垂直于连接线的方向（主要是拉伸）上对应力分量的增强效果明显小于在连接线的方向（主要是压缩）上的增强效果。 。而且，这些应力增强不足以在井眼之间的应力波叠加区域中引起裂纹萌生。数值模拟分析进一步表明，应力波叠加区的裂纹萌生对爆炸参数，岩石特性和井眼间距有相对严格的要求，在工程实践和模型实验中很难观察到。但是在垂直于连接线的方向（主要是拉伸）上对应力分量的增强作用明显小于在连接线的方向（主要是压缩）上的应力作用。而且，这些应力增强不足以在井眼之间的应力波叠加区域中引起裂纹萌生。数值模拟分析进一步表明，应力波叠加区的裂纹萌生对爆炸参数，岩石特性和井眼间距有相对严格的要求，在工程实践和模型实验中很难观察到。但是在垂直于连接线的方向（主要是拉伸）上对应力分量的增强作用明显小于在连接线的方向（主要是压缩）上的应力作用。而且，这些应力增强不足以在井眼之间的应力波叠加区域中引起裂纹萌生。数值模拟分析进一步表明，应力波叠加区的裂纹萌生对爆炸参数，岩石特性和井眼间距有相对严格的要求，在工程实践和模型实验中很难观察到。这些应力的增强不足以在井眼之间的应力波叠加区域中引起裂纹萌生。数值模拟分析进一步表明，应力波叠加区的裂纹萌生对爆炸参数，岩石特性和井眼间距有相对严格的要求，在工程实践和模型实验中很难观察到。这些应力的增强不足以在井眼之间的应力波叠加区域中引起裂纹萌生。数值模拟分析进一步表明，应力波叠加区的裂纹萌生对爆炸参数，岩石特性和井眼间距有相对严格的要求，在工程实践和模型实验中很难观察到。