Sensitivity analysis on blast design parameters to improve bench blasting outcomes using the Taguchi method

In surface mines, bench blasting is a typical way of excavating hard rock mass. Although a significant development has taken place in explosive technology but still only a part of the energy is used to excavate and a large proportion of energy is wasted away and creates a number of nuisances. Backbreak, massive rock fragmentation, and high-intensity ground vibration are all symptoms of improper blasting. As a result, production costs increase significantly while productivity decreases. The blasting outcomes are affected by a variety of factors, which may be classified into three categories: rock properties, explosive properties, and blast geometry. Consequently, it is necessary to examine the effect of these parameters on bench blasting. So, in this study, a sensitivity analysis has been performed on various blast design parameters using the Taguchi method to study the influence of blast design parameters on blast vibration, backbreak, and rock fragmentation. A total of 32 experiments have been designed and numerical modeling was also carried out, using LS DYNA software to simulate the blast results. It was found that the blast hole diameter is the most important factor influencing the blasting outcomes. However, the number of rows in a blast affects backbreak almost slightly more than the hole diameter, but blast vibrations and the surrounding rock damage strongly depend on the hole diameter. Furthermore, rock blast geometry significantly affected rock blast vibration and damage compared to explosive properties. However, both blast geometry parameters and explosive properties play a significant role in backbreaking. Highlights The Taguchi method has been applied to study the influence of various blast design parameters on blast vibration, back break, and rock fragmentation. According to sensitivity analysis, it was observed that the hole diameter is the most important parameter that affects blasting results. In large diameter holes, the energy released by explosives is greater than the small diameter holes and due to that, a higher PPV occurred. As a result, PPV is affected primarily by hole diameter and charge weight. It was observed that an increase in charge weight does not necessarily increase the PPV but the other design parameters also affect it. Thus, increasing charge weight can increase rock crushing, while modifying other blasting parameters can reduce ground vibrations. The effect of the powder factor on backbreak is greater than that of the ge