摘要
为了研究粒径对风化壳淋积型稀土矿强度特性的影响及其机理,以制备的四种粒径稀土矿样为研究对象,开展不同正应力下直剪实验和XRD测试,分析粒径对稀土矿石剪切强度的影响规律,揭示粒径对黏聚力与内摩擦角的影响作用机理。结果表明:同一正应力条件下,矿样剪切强度随粒径增大而增大,且剪切应力峰值出现的时间随粒径增大而变短;剪切位移随粒径增大而减小;利用回归分析方法,构建粒径与黏聚力和内摩擦角的关系模型;<0.075 mm矿样中黏土矿物比例最大,颗粒表面间形成较厚的结合水膜,剪切强度最小,而>0.45 mm矿样中石英和长石等非黏土矿物比例最大,颗粒间摩擦作用大,剪切强度最大。研究成果可为预防和控制风化壳淋积型稀土矿边坡失稳提供理论依据。
In order to study the influence of particle size on the strength characteristics and its mechanism,four kinds of prepared rare earth ore samples with different particle size were taken as research objects.The direct shear tests under different normal stress and XRD tests were carried out to analyze the effect of particle size on the shear strength of rare earth ore and reveal the influence mechanism of particle size on the cohesion and internal friction angle.The results showed that the shear strength of ore samples increased with the increase of particle size and the time of the shear stress peak decreased with the increase of particle size under the same normal stress condition.The shear displacement decreased with the increase of particle size.The relation model between particle size and cohesion and internal friction angle was established by means of regression analysis.The proportion of clay minerals in-0.075 mm ore samples was the largest,and a thick bound water film was formed between the particle surfaces,and its shear strength was the minimum.While the proportion of non-clay minerals such as quartz and feldspar in+0.45 mm ore samples with a large interparticle friction effect was the largest,and its shear strength was the maximum.The research results provide a theoretical basis for preventing and controlling the slope instability of the weathered crust elution-deposited rare earth ores.
作者
刘德峰
张臻悦
池汝安
席银龙
颜肃
LIU Defeng;ZHANG Zhenyue;CHI Ru’an;XI Yinlong;YAN Su(School of Resources and Safety Engineering,Wuhan Institute of Technology,Wuhan 430073,China;Hubei Research and Design Institute of Chemical Industry,Wuhan 430073,China;Key Laboratory of Green Chemical Engineering Process of Ministry of Education,Wuhan Institute of Technology,Wuhan 430073,China)
出处
《有色金属工程》
CAS
北大核心
2020年第6期97-103,共7页
Nonferrous Metals Engineering
基金
国家自然科学基金资助项目(U1802252,91962211,21808176)
科技部重点研发计划项目(2018YFC1801800)
中国博士后科学基金(2019M662577)
湖北省教育厅基金(Q20191502,Q20191503)
武汉工程大学基金(18QD50,18QD57)。
关键词
稀土矿
粒径
剪切强度
黏聚力
内摩擦角
rare earth ores
particle size
shear strength
cohesion
internal friction angle
