To optimize the excavation of rock using underground blasting techniques, a reliable and simplified approach for modeling rock fragmentation is desired. This paper presents a multistep experimentalnumerical methodology for simplifying the three-dimensional (3D) to two-dimensional (2D) quasiplane-strain problem and reducing computational costs by more than 100-fold. First, in situ tests were conducted involving single-hole and free-face blasting of a dolomite rock mass in a 1050-m-deep mine. The results were validated by laser scanning. The craters were then compared with four analytical models to calculate the radius of the crushing zone. Next, a full 3D model for single-hole blasting was prepared and validated by simulating the crack length and the radius of the crushing zone. Based on the stable crack propagation zones observed in the 3D model and experiments, a 2D model was prepared. The properties of the high explosive (HE) were slightly reduced to match the shape and number of radial cracks and crushing zone radius between the 3D and 2D models. The final methodology was used to reproduce various cut-hole blasting scenarios and observe the effects of residual cracks in the rock mass on further fragmentation. The presence of preexisting cracks was found to be crucial for fragmentation, particularly when the borehole was situated near a free rock face. Finally, an optimization study was performed to determine the possibility of losing rock continuity at different positions within the well in relation to the free rock face. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).
The tensile -shear interactive damage (TSID) model is a novel and powerful constitutive model for rocklike materials. This study proposes a methodology to calibrate the TSID model parameters to simulate sandstone. The basic parameters of sandstone are determined through a series of static and dynamic tests, including uniaxial compression, Brazilian disc, triaxial compression under varying confining pressures, hydrostatic compression, and dynamic compression and tensile tests with a split Hopkinson pressure bar. Based on the sandstone test results from this study and previous research, a step-by-step procedure for parameter calibration is outlined, which accounts for the categories of the strength surface, equation of state (EOS), strain rate effect, and damage. The calibrated parameters are verified through numerical tests that correspond to the experimental loading conditions. Consistency between numerical results and experimental data indicates the precision and reliability of the calibrated parameters. The methodology presented in this study is scientifically sound, straightforward, and essential for improving the TSID model. Furthermore, it has the potential to contribute to other rock constitutive models, particularly new user -defined models. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).