朱昌星, 霍嘉鑫, 吴大志,等.分形煤岩胶结体动态力学性能及数值模拟研究[J].河南理工大学学报（自然科学版）,2025,44(4):112-123.

ZHU C X, HUO J X, WU D Z, et al. Dynamic mechanical properties and numerical simulation of fractal coal-rock cemented bodies [J]. Journal of Henan Polytechnic University (Natural Science) , 2025, 44(4): 112-123.

分形煤岩胶结体动态力学性能及数值模拟研究

朱昌星, 霍嘉鑫, 吴大志

河南理工大学 土木工程学院，河南 焦作 454000

摘要: 目的 为研究颗粒破碎程度对煤岩胶结体的动态力学性能影响， 方法 基于松散介质固体颗粒分布规律理论，以分形维数分别为1.4，1.7，2.0，2.3，2.6配制不同破碎程度的松散煤体，按比例将胶凝材料与煤体拌合，经养护后制成标准块，对其进行分离式霍普金森压杆冲击试验，并利用有限元软件LS-DYNA对SHPB试验过程进行数值模拟和对比分析。 结果 结果表明，分形维数D=1.7时，抗压强度最低、分形维数D=2.6时，抗压强度最高；煤岩破碎程度对试样的动态力学性能影响较大；水泥基体内能远大于4种粒径煤体内能之和；数值模拟的峰值应力、应变终值和破坏模式与室内试验结果吻合较好。粒径为0~20 mm时，0~5 mm的小颗粒质量占比越多，试样整体强度越高；胶结体动态抗压强度随着分形维数增大先减小后增大；动态压缩下试块耗散能也呈先减后增趋势；分形维数D=1.7的煤体级配不利于发挥胶结体试块的力学性能；水泥基体为主要的储能介质，承担主要的能量吸收与耗散；HJC参数的合理选取可以使数值模拟较好地反映胶结体试块的动态力学特性。 结论 研究结果可为后续煤岩注浆提供一定的技术支持。 

关键词:煤体破碎程度;胶结体;分离式霍普金森压杆;动态抗压强度;数值模拟

doi: 10.16186/j.cnki.1673-9787.2024030053

基金项目:国家自然科学基金资助项目（51874119）；安全学科双一流创建课题培育项目基金资助项目（AQ20240726）；河南理工大学博士基金资助项目（B2009-96）

收稿日期:2024/03/19

修回日期:2024/06/21

出版日期:2025/06/19

Dynamic mechanical properties and numerical simulation of fractal coal-rock cemented bodies

Zhu Changxing, Huo Jiaxin, Wu Dazhi

School of Civil Engineering， Henan Polytechnic University， Jiaozuo 454000， Henan， China

Abstract: Objectives To investigate the influence of particle breakage degree on the dynamic mechanical properties of coal-rock cemented bodies. Methods Based on the theory of solid particle distribution in loose media， loose coal samples with varying degrees of fragmentation were prepared using fractal dimensions of 1.4， 1.7， 2.0， 2.3， and 2.6. These were mixed with cementitious materials in proportion and cured to form standard specimens. Split Hopkinson Pressure Bar （SHPB） tests were conducted to evaluate the dynamic properties， and the SHPB test process was simulated using the finite element software LS-DYNA for comparative analysis. Results The compressive strength was found to be the lowest at a fractal dimension of 1.7 and the highest at 2.6. The degree of coal fragmentation significantly affected the dynamic mechanical behavior of the specimens. The internal energy of the cement matrix was considerably greater than the combined internal energy of coal particles of different sizes. Numerical simulation results-including peak stress， final strain， and failure modes-were in good agreement with the experimental results. Within the particle size range of 0~20 mm， specimens with a higher mass proportion of 0~5 mm fine particles exhibited greater overall strength. The dynamic compressive strength of the cemented body decreased initially and then increased with increasing fractal dimension. Similarly， the energy dissipation under dynamic compression also showed a decrease-increase trend. A gradation corresponding to a fractal dimension of 1.7 was found to be unfavorable for the mechanical performance of the cemented body. The cement matrix served as the primary energy storage and dissipation medium. Reasonable selection of HJC model parameters allowed the numerical simulation to accurately reflect the dynamic mechanical behavior of the cemented specimens. Conclusions The findings provide technical support for future coal and rock grouting practices. 

Key words: coal fragmentation degree; cemented body; Split Hopkinson Pressure Bar; dynamic compressive strength; numerical simulation