Prediction of blasting fragmentation based on geological characterization of in-situ rock mass discontinuities

In mining metal deposits, blasting fragmentation is a key indicator that directly affects production efficiency and economic costs. To address the limitations of current post-blast assessment, which overlooks the intrinsic relationship between in-situ fragmentation (geological characterization of in-situ rock mass discontinuities) and the resulting blasting fragmentation, this paper proposes a quantitative prediction model and methodology for blasting fragmentation. Through field investigation of discontinuities and three-dimensional discontinuity network modeling, the in-situ fragmentation of rock mass was characterized. Combined with rock breakage characteristics under blasting loads, a fractal-based model was established to predict blasting fragmentation from in-situ fragmentation, yielding a quantitative prediction framework. Across the full size distribution, validation through an engineering case study showed an RMSE of 6.611% and a MAPE of 4.393% between the predicted and measured cumulative fragmentation percentages. The results indicate engineering applicability and provide a quantitative prediction methodology for blasting fragmentation, particularly for boulder yield prediction.