废石颗粒级配优化对充填材料性能的影响机制  

Influence mechanism of optimization of waste stone particle gradation on the performance of filling materials

作　　者：刘德峰 崔晨冉 郑彦涛 王良群 姜贵川 LIU Defeng;CUI Chenran;ZHENG Yantao;WANG Liangqun;JIANG Guichuan(Engineering Technology Research Center of National Phosphorus Resources Development and Utilization,Wuhan Institute of Technology,Wuhan 430073,China;Guizhou Xifeng Phosphate Rock Co.,Ltd.,Guiyang 550001,China)

机构地区：[1]武汉工程大学国家磷资源开发利用工程技术研究中心,武汉430073 [2]贵州息烽磷矿有限责任公司,贵阳550001

出　　处：《有色金属（矿山部分）》2024年第5期93-102,共10页NONFERROUS METALS(Mining Section)

基　　金：黔科合成果项目([2023]一般777);国家磷资源开发利用工程技术研究中心开放基金(LKF202005)。

摘　　要：目的:减少排土场废石堆积对矿山产生的安全威胁。方法:通过研究废石颗粒粒径分布特征,进行不同级配废石胶结充填材料的力学特性及流动性能实验,优化废石颗粒级配,揭示其与水泥及粉煤灰固化作用机制。结果:+0.075~-16 mm废石充填体试件的颗粒级配分布特征与机制砂充填体强度特性相近,其单轴抗压和抗拉强度及软化系数均高于其余废石级配充填体;四种充填料浆的坍落度相差不大,而+0.075~-16 mm废石充填料浆的泌水率较小,流动性较好;养护28 d废石(+0.075~-16 mm)充填体试件表面较平整,微观结构较紧密,其内部被少量的废石颗粒和粉煤灰、较多的网络状水化硅酸钙(C-S-H)凝胶和大量的针棒状钙矾石(AFt)水化产物,以及六方板状的CH晶体结构充填,使得其微观结构比其余废石(-16 mm和+0.15~-16 mm)试件更加致密,与机制砂(-16 mm)试件相接近。结论:既能为类似矿山优化充填工艺参数提供技术借鉴,也可以减少矿山充填开采成本。Purpose:reduce the safety threat of waste rock accumulation in the waste dump.Method:the particle size distribution characteristics of waste rock were studied.Both the mechanical properties and flow performance of cementitious filling materials with different graded waste rocks were analyzed.The particle size distribution of waste rock was optimized,and its mechanism of action with cement and fly ash solidification was revealed.Results:the particle size distribution characteristics of the+0.075~-16 mm waste rock filling specimen were similar to the strength characteristics of the mechanized sand filling body.Their uniaxial compressive and tensile strength,as well as softening coefficient,were higher than those of other waste rock graded filling bodies.The slump of the four types of filling slurry was not significantly different,while the bleeding rate of the+0.075~-16 mm waste stone filling slurry was small and the flowability was good.After 28 days of curing,the surface of the filling specimen of waste rock(+0.075~-16 mm)was flat and the microstructure was compact.The interior of the filling specimen was filled with a small number of waste rock particles and fly ash,more network like calcium silicate hydrate(C-S-H)gel,a large number of needle bar like ettringite(AFt)hydration products,and hexagonal plate like CH crystal structure.It made its microstructure more compact than the waste rock(-16 mm and+0.15~-16 mm)specimens.And it was similar to the mechanized sand(-16 mm)specimens.Conclusion:the research results can provide technical reference for optimizing filling process parameters in similar mines,and can also reduce the cost of mining filling.

关 键 词：废石 颗粒级配 胶结充填 抗压强度 流动性 微观结构 

分 类 号：TD95[矿业工程—选矿]