###### Abstract  
Blasting technology is widely applied in various engineering applications due to its cost-effectiveness and high efficiency, such as in mining, transport infrastructure construction, and building demolition. However, the occurrence of cracking in the rear row has always been a major problem that disrupts mining bench blasting. To address this issue, a three-hole simultaneous blasting technology is proposed in this study. Both numerical simulations and onsite blasting experimental testing were conducted. To aid this endeavor, the three-hole simultaneous blasting and the hole-by-hole blasting methods were adopted to comparatively analyze the severity of the damage caused to the original rock and the effect of rock fragmentation in the rear row. The obtained results highlighted that the outcome of the blast produced by the three-hole simultaneous blasting method is satisfactory, with fewer flying stones and concentrated blasting piles required. Additionally, the original rock in the rear row showed no obvious sign of tensile damage and had uniform fragmentation. It was also found that a block size of less than 60 cm accounts for 100%, while a block size of less than 50 cm accounts for 98.7% of the whole blocks, with no large blocks reported. Moreover, a penetrating horizontal crack occurred in the direction of the connection of the blast hole center when the three-hole simultaneous blasting method was adopted. This resulted in a smooth and flat rear part of the rocks at the interface. Compared to the hole-by-hole blasting method, the three-hole simultaneous blasting method improved the effective stress and displacement at each measurement point. At the measurement point directly at the front of the borehole, the maximum effective stress attained 67.9 GPa, and the maximum displacement reported was 31.9 cm. Overall, it was shown that the three-hole simultaneous blasting technology is applicable in similar applications of mine bench blasting, which is conducive to addressing the rear row original rock strain for onsite bench blasting. s 2024 1  
When determining the optimum delay time in multihole blasting, except for the stress wave interaction, key factors such as crack propagation should be considered. [PERSON] et al. [9] examined the open-cut bench blasting at the Barun Eboxi Mine of the Baotou Iron and Steel Group by conducting a theoretical analysis of the shock wave, performing numerical simulations, and carrying out field tests. The study found that under the condition of a 24 m high bench, the use of intermediate air intervals is beneficial to rock fragmentation. In another work, [PERSON] et al. [10] examined the effect of several blasting parameters on bench blasting. A total of 32 experiments have been designed and conducted, and numerical simulations were also carried out using the LS DYNA (R14.0) software to evaluate the blast results. As a result, it was reported that the blast hole diameter is the most important factor influencing blasting outcomes. [PERSON] et al. [11] used the random forest algorithm to develop a model for predicting the blast-induced ground vibrations from bench blasting using 48 dataset records. The model was trained and tested by employing the WEKA data-mining software (3.9.5). The study results demonstrated that the random forest model can effectively predict the peak particle velocity (PPV). Additionally, it was noted that the equivalent-path-based equation is a suitable empirical method for predicting the PPV. In their study, [PERSON] et al. [12] used digital electronic detonators in large-scale iron ore mining. The implementation not only improved the outcome of blasting but also reduced the damage caused by blasting vibrations. As a result, a higher shovel efficiency was reported. In a connected study, [PERSON] et al. [13] used a digital electronic detonator for the excavation of high-side slopes. It was shown that this approach is effective in reducing blasting vibrations and high block rates and lowering the workload of secondary crushing. Also, [PERSON] et al.