Wei Sijiang, Li Jianjun, Wang Meng, Yu ChunSheng
Henan Key Laboratory of Green and Efficient Mining and Comprehensive Utilization of Mineral Resources, Henan Polytechnic University, Jiaozuo 454000, China.
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China.
ACS Omega. 2025 May 1;10(18):18744-18752. doi: 10.1021/acsomega.5c00300. eCollection 2025 May 13.
The surrounding rock of the bottom drainage roadway at the Guhanshan Coal Mine is composed of hard sandstone, characterized by structural integrity and high strength. However, due to an inadequate basis for parameter selection during presplitting blasting to aid rock breaking, the overall excavation efficiency is low. To address this issue, this study calculates the equation-of-state parameters for the Holmquist-Johnson-Cook (HJC) constitutive model. These parameters are derived using the basic physical and mechanical parameters of the hard sandstone samples from the bottom drainage roadway at the Guhanshan Coal Mine, combined with the theoretical approach for determining HJC model parameters. Using the obtained parameters, LS-DYNA software is used to conduct numerical simulation research on the dynamic impact of sandstone. The simulation captures the physical and mechanical responses of intact sandstone samples under varying impact velocities. The results demonstrate that the stress-strain curves from indoor experiments closely align with simulation outcomes. During the loading process, specimen cracks initiate at the center and propagate toward the edges. Tensile cracks initiate and gradually expand until specimen failure, addressing the deficiency of the physical experiment observations. The HJC constitutive model effectively represents the mechanical behavior of sandstone samples under different impact velocities. The particle size, crack width, and penetration of the fractured specimen effectively characterize the rate effect of the impact dynamic load. These parameters show a positive correlation with the loading speed. Numerical simulations of presplitting blasting were conducted on rock models with varying borehole layout configurations using the calibrated constitutive model parameters. The results demonstrate that under identical charge parameters, the equilateral triangular borehole layout configuration achieves the most extensive damage propagation. Therefore, the equilateral triangular borehole arrangement is recommended as the optimal configuration for presplitting blasting in the bottom drainage roadway of Guhanshan Coal Mine.
古汉山煤矿底部排水巷道的围岩由坚硬砂岩组成，具有结构完整、强度高的特点。然而，由于在预裂爆破辅助破岩过程中参数选择依据不足，整体开挖效率较低。为解决这一问题，本研究计算了霍姆奎斯特 - 约翰逊 - 库克（HJC）本构模型的状态方程参数。这些参数是利用古汉山煤矿底部排水巷道坚硬砂岩样品的基本物理力学参数，并结合确定HJC模型参数的理论方法推导得出的。利用所获得的参数，运用LS - DYNA软件对砂岩的动态冲击进行数值模拟研究。该模拟捕捉了完整砂岩样品在不同冲击速度下的物理力学响应。结果表明，室内实验得到的应力 - 应变曲线与模拟结果紧密吻合。在加载过程中，试样裂纹从中心开始并向边缘扩展。拉伸裂纹产生并逐渐扩展直至试样破坏，弥补了物理实验观测的不足。HJC本构模型有效地表征了砂岩样品在不同冲击速度下的力学行为。破碎试样的粒径、裂纹宽度和穿透情况有效地表征了冲击动载荷的速率效应。这些参数与加载速度呈正相关。利用校准后的本构模型参数，对不同炮孔布置形式的岩石模型进行了预裂爆破数值模拟。结果表明，在相同装药参数下，等边三角形炮孔布置形式的损伤传播范围最广。因此，建议将等边三角形炮孔布置作为古汉山煤矿底部排水巷道预裂爆破的最优布置形式。
