陈岩,王嘉豪, 邓良涛,等.不同加载速率对煤岩组合体巴西劈裂特性的影响[J].河南理工大学学报（自然科学版）,2025,44(1):29-36.

CHEN Y,WANG J H, DENG L T, et al. Effects of varying loading rates on the Brazilian splitting characteristics of coal-rock composites[J]. Journal of Henan Polytechnic University(Natural Science) , 2025, 44(1): 29-36.

不同加载速率对煤岩组合体巴西劈裂特性的影响

陈岩1,2,王嘉豪1, 邓良涛1, 洪紫杰3, 荣腾龙1,2,侯志强1

1.河南理工大学 能源科学与工程学院，河南 焦作  454000;2.煤炭安全生产与清洁高效利用省部共建协同创新中心，河南 焦作  454000;3.河南理工大学 土木工程学院，河南 焦作  454000

摘要: 目的 为了研究煤岩组合体在采掘过程中的抗拉特性， 方法 以煤岩组合体为研究对象，利用RMT-150B实验机对其进行不同加载速率下的巴西劈裂试验，分析加载速率对煤岩组合体劈裂破坏的强度特征、破坏形态、能量特征和裂纹演化的影响。 结果 结果表明：煤岩组合体的应力-应变曲线大致经历了压密阶段、弹性阶段、屈服阶段、破坏阶段，其破坏模式与加载速率无关，均沿着圆盘交界面裂成两半；煤岩组合体的抗拉强度与加载速率呈正相关，加载速率较小时，试样的抗拉强度随加载速率变化十分显著；当加载速率增大时，试样的抗拉强度增幅减小；不同加载速率下，煤岩组合体试样的能量集中在0.33~0.42 J，且试样抗拉强度越大，损伤所需的能量也越大；应力-裂纹应变峰前曲线经历裂纹闭合阶段、弹性阶段、裂纹扩展阶段，轴向裂纹损伤应力与抗拉强度值接近，裂纹参数具有明显的加载速率效应。 结论 研究结果对于揭示煤岩组合结构拉伸破坏机理具有重要理论价值。

关键词:煤岩组合体;巴西劈裂;强度特征;能量特征;裂纹演化

doi: 10.16186/j.cnki.1673-9787.2023100027

基金项目:国家自然科学基金资助项目（5190409,52274078，52304084）；河南省高等学校重点科研项目（24A440004）

收稿日期:2023/10/13

修回日期:2024/03/08

出版日期:2025/01/02

Effects of varying loading rates on the Brazilian splitting characteristics of coal-rock composites

CHEN Yan1,2,WANG Jiahao1, DENG Liangtao1, HONG Zijie3, RONG Tenglong1,2,HOU Zhiqiang1

1. School of Energy Science and Engineering， Henan Polytechnic University， Jiaozuo  454000， Henan， China; 2. Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization， Jiaozuo  454000， Henan， China ; 3. School of Civil Engineering， Henan Polytechnic University， Jiaozuo  454000， Henan， China

Abstract: Objectives To investigate the tensile characteristics of coal-rock composite structures during the mining process， the study takes coal-rock composite specimens as the research object.  Methods Brazilian splitting tests were conducted on coal-rock composite specimens under varying loading rates using the RMT150B testing machine. The effects of loading rates on the strength characteristics， failure modes， energy features， and crack evolution during splitting failure were analyzed. Results The stress-strain curves of the coal-rock composites generally followed four stages： compaction， elasticity， yield， and failure. The fai-lure mode was independent of the loading rate， with all specimens splitting along the interface of the disks. The tensile strength of the composite increased with loading rate， showing significant changes under low loading rates， while the rate of increase diminished as the loading rate became higher. The energy concentration in coal-rock composite specimens ranged from 0.33 J to 0.42 J， and higher tensile strength required greater energy for failure. The stress-crack strain curve exhibited three stages before the peak： crack closure， elasticity， and crack propagation. The crack parameters demonstrated a pronounced dependency on loading rates. Conclusions These findings provide valuable theoretical insights into the tensile failure mechanism of coal-rock composite structures.

Key words: coal-rock composites; Brazilian splitting; strength characteristics; energy features; crack evolution