张超, 汤杰,刘勇锋,等.冻融循环作用下尾矿宏观力学损伤与微观结构影响研究[J].河南理工大学学报（自然科学版）,2025,44(6):9-17.

ZHANG C, TANG J, LIU Y F,et al.Macromechanical damage and microstructural effects of tailings under freeze-thaw cycles[J].Journal of Henan Polytechnic University(Natural Science) ,2025,44(6):9-17.

冻融循环作用下尾矿宏观力学损伤与微观结构影响研究

张超1,2, 汤杰1,2,3, 刘勇锋4,5, 马昌坤2, 陈青林1,3, 曾鹏1,3

1.江西理工大学 资源与环境工程学院，江西 赣州  341000；2.中国科学院武汉岩土力学研究所 岩土力学与工程安全全国重点实验室，湖北 武汉  430071；3.稀有金属资源安全高效开采江西省重点实验室，江西 赣州  341000；4.重庆大学 资源及环境科学学院，重庆  400044；5.深圳市中金岭南有色金属股份有限公司，广东 深圳  518024

摘要: 目的 为揭示冻融循环作用下尾矿的宏-微观损伤机制，开展冻融循环作用下尾矿宏观力学损伤与微观结构影响研究。  方法 通过三轴固结不排水剪切试验、扫描电镜（SEM）和微米CT扫描试验，研究冻融循环次数对尾矿力学性能和微观结构的影响规律，并建立宏观力学损伤与微观结构演化的关联机制。  结果 结果表明：冻融循环导致尾矿宏观力学特性显著劣化，峰值抗剪强度经1次冻融后降幅达13.35%；5~10次冻融循环阶段的峰值强度下降率为8.8%；10~15次循环阶段峰值降幅减小至3.9%。经15次冻融循环后，黏聚力与内摩擦角分别降低50.9%，59.3%。冻融循环作用导致尾矿颗粒棱角磨损及形态圆润化，形状因子由1.38下降至1.34；孔隙分形维度从1.55增至1.64，孔隙率由8.9%上升至16.91%，其中连通孔隙占比从4.68%显著提升至15.51%.研究进一步揭示了孔隙率与抗剪强度呈非线性负相关，内摩擦角随颗粒形状因子增大呈指数增长规律。 结论 研究结果可为冻土区尾矿库稳定性分析及灾害防控提供参考。

关键词:尾矿;冻融循环;力学损伤;微观结构

doi:10.16186/j.cnki.1673-9787.2025030063

基金项目:国家重点研发计划项目（2023YFC3012200）；国家自然科学基金资助项目（52304155）；江西省自然科学基金资助项目（20232BAB213069）；宜春市重大科技攻关项目（2023ZDKJGG04）

收稿日期:2025/03/28

修回日期:2025/05/19

出版日期:2025/1014

Macromechanical damage and microstructural effects of tailings under freeze-thaw cycles

Zhang Chao1,2, Tang Jie1,2,3, Liu Yongfeng4,5, Ma Changkun2, Chen Qinglin1,3, Zeng Peng1,3

1.School of Resources and Environmental Engineering， Jiangxi University of Science and Technology， Ganzhou  341000， Jiangxi， China；2.State Key Laboratory of Geomechanics and Geotechnical Engineering Safety， Institute of Rock and Soil Mechanics， Chinese Academy of Sciences， Wuhan  430071， Hubei， China；3.Jiangxi Provincial Key Laboratory of Safe and Efficient Mining of Rare Metal Resource， Ganzhou  341000， Jiangxi， China；4.School of Resources and Safety Engineering， Chongqing University， Chongqing  400044， China；5.Shenzhen Zhongjin Lingnan Non-ferrous Metal Company Limited， Shenzhen  518024， Guangdong，China

Abstract: Objectives This study aims to reveal the macro-micro damage mechanisms of tailings materials under freeze-thaw cycling. Methods Through triaxial consolidated undrained shear tests， scanning electron microscopy （SEM）， and micro-CT scanning， the effects of freeze-thaw cycle frequency on the mechanical properties and microstructural evolution of tailings were investigated. A correlation mechanism between macroscopic mechanical damage and microstructural changes was established.  Results Freeze-thaw cycles significantly degraded the macroscopic mechanical properties of tailings. The peak shear strength decreased by 13.35% after one freeze-thaw cycle. During the 5~10 cycle stage， the peak strength reduction rate was 8.8%， while in the 10~15 cycle stage， the reduction rate decreased to 3.9%. After 15 cycles， cohesion and internal friction angle decreased by 50.9% and 59.3%， respectively. Freeze-thaw cycling caused particle edge abrasion and rounding， with the shape factor decreasing from 1.38 to 1.34. The pore fractal dimension increased from 1.55 to 1.64， porosity rose from 8.9% to 16.91%， and the proportion of connected pores increased markedly from 4.68% to 15.51%. Furthermore， porosity exhibited a nonlinear negative correlation with shear strength， while the internal friction angle showed an exponential increase with particle shape factor. Conclusions These findings provide a scientific basis for stability analysis and disaster prevention of tailings dams in permafrost regions.

Key words: tailings; freeze-thaw cycle; mechanical damage; microstructure