循环单剪下间断级配人工粗粒料形状演化研究  

Study on Shape Evolution of Gap-graded Artificial Coarse Granular Materials Under Cyclic Simple Shear

作　　者：刘宇轩 沈超敏[1] 刘辰耕 吴志刚 徐熊 胡继峰 李健 甘元楠 LIU Yu-xuan;SHEN Chao-min;LIU Chen-geng;WU Zhi-gang;XU Xiong;HU Ji-feng;LI Jian;GAN Yuan-nan(College of Water Resources and Hydropower,Hohai University,Nanjing 210098,Jiangsu Province,China;China Safety Energy Group Second Engineering Bureau Co.,Ltd.,Nanchang 330095,Jiangxi Province,China)

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]中国安能集团第二工程局有限公司,江西南昌330095

出　　处：《中国农村水利水电》2025年第3期159-165,共7页China Rural Water and Hydropower

基　　金：国家自然科学基金(52009036,51979091);云南省重点科技攻关项目(202202AF080003)。

摘　　要：为了详细揭示间断级配粗粒料颗粒在循环剪切作用下的形状演化规律,使用人工染色石膏颗粒进行了不同剪切次数下的单剪试验,并采用激光扫描仪获取了颗粒的三维形状。结果表明:间断级配粗粒料中,小颗粒对大颗粒具有打磨变圆的作用,表现为大颗粒具有更低的延伸率、更大的球形度和磨圆度;随着剪切次数的增加,大、小粒径的存活颗粒(破碎后仍处于原粒径组的颗粒)先后经历碎裂破坏,但是最终颗粒形状均趋向于规则;迁移颗粒(破碎产生的颗粒)的形状随剪切次数的增加也逐渐趋向于规则,但与相同粒径的存活颗粒相比仍具有较大的差异,说明使用整体级配泛化描述颗粒的破碎行为是不合适的;大颗粒的形状更倾向于球状和扁平状,而小颗粒更容易形成球状和柱状;SH重构颗粒的形状参数分布与真实状态极为相似,部分形状参数之间存在较强的线性相关性。研究结果可为阐明颗粒形状保护机制以及构建形状演化模型提供参考。To comprehensively reveal the shape evolution of gap-graded coarse granular particles under cyclic shear,a series of simple shear tests were conducted using artificially dyed gypsum particles at different shear cycles,and the 3D shape of the particles was obtained using a laser scanner.The results show that within the gap-graded coarse materials,smaller particles exert a grinding and rounding effect on larger particles,manifested by lower elongation,greater sphericity,and roundness of the larger particles.With the increase of shear cycles,both larger and smaller diameter surviving particles(particles that remain within their original size range after breakage)successively undergo fracture damage,but eventually the final particle shapes tend towards regularity.Conversely,the shape of migrated particles(particles generated from breakage)gradually approach regularity with increasing shear cycles,yet still exhibit significant differences compared to surviving particles of the same size.This suggests that using generalized descriptions of particle breakage behavior based on whole gradation is inappropriate.The shape of larger particles tend towards spherical and flattened shapes,while smaller particles more readily assume spherical and columnar shapes.The shape parameter distribution of SH reconstructed particles closely resembles their real state,and strong linear correlations exist between some shape parameters.These research results can provide a reference for understanding the particle shape protection mechanism and constructing the shape evolution model.

关 键 词：颗粒破碎 间断级配 循环单剪 染色示踪 三维形状 球谐函数 

分 类 号：TV41[水利工程—水工结构工程]