Comprehensive evaluation of shaped charge blasting effect of rock roadway based on entropy-weighted matter-element extension model

In order to accurately evaluate the cumulative blasting effect of roadway, an entropy-weighted matter-element extension model was introduced to evaluate the blasting effect. Through the analysis of blasting quality, blasting economic and technical benefits, and blasting safety, 12 indexes such as bulk rate, blasting shape, and explosive consumption were selected to build a comprehensive evaluation model. Then, in order to avoid the uncertainty of subjective weighting method in the evaluation process, the entropy weighting method was introduced to determine the weight coefficient of matter-element index. Finally, the model is applied to the blasting example of Kong Zhuang coal mine, and the grading of blasting effect is evaluated qualitatively and quantitatively. Results show that the evaluation of the model is consistent with the actual grade. In addition, compared with ordinary smooth blasting, cumulative blasting can reduce the explosive consumption by 27%, increase the blasthole utilization rate to 97.1%, and improve the forming quality of roadway.