全尾砂胶结充填材料自流管输与力学性能及机理研究

Self-flowing pipeline transportation, mechanical properties and mechanisms of full-tailings cemented backfill materials

  • 摘要: 在矿山胶结充填中,充填材料的管输与力学性能直接影响充填系统能否成功应用。为研究全尾砂胶结充填材料的自流管输与力学性能,开展L管试验和充填体强度试验,分析充填材料性能的变化规律与微观机理,讨论工业应用的可行性。研究结果表明:随胶结剂添加量和料浆质量分数增加,屈服应力或管输阻力分别降低和增大,而黏度与充填体强度均增大,最大充填倍线与管输阻力呈负相关;颗粒间的吸引力变大与颗粒间的摩擦加剧分别是屈服应力与黏度增大的内因,屈服应力引起管输阻力变化超过黏度对其的影响;随试验因素单独或同时增加,水化产物数量增多且孔隙面积减小,结构密实性得到改善,充填体强度提高;在胶结剂添加量和料浆质量分数分别为210 kg/m3与68 % 时,最大充填倍线和充填体28 d强度的富余度分别约为4.11 % 和2.08 %,兼具工业适用性与经济性。研究成果为胶结充填材料自流输送理论与工艺提供参考。

     

    Abstract: In mine cemented backfill, the pipeline transportation and mechanical properties of backfill materials are pivotal for the successful application of the backfill system. This study therefore investigates the self-flowing pipeline transportation and mechanical properties of full-tailings cemented backfill materials through L-pipe and strength tests. The variation patterns and microscopic mechanisms of backfill properties were analyzed and the feasibility of its industrial applications was discussed. Results show that increasing binder content and slurry mass concentration led to decreasing yield stress and increasing pipeline transportation resistance. As the viscosity and strength of backfill body increased, the maximum filling gradient was negatively correlated with pipeline transportation resistance. Intensified interparticle attraction and exacerbated interparticle friction were the intrinsic causes for the rise in yield stress and viscosity, as yield stress exerted a dominant influence on pipeline transportation resistance than viscosity. Individual or simultaneous increase in test factors leads to increased quantity of hydration products, reduced pore area, improved structural compactness and strength. With binder content of 210 kg/m3 and slurry mass concentration of 68 %, the system exhibited both industrial adaptability and economic efficiency, achieving a 4.11 % surplus in maximum filling gradient and 28 d strength of 2.08 %. This study offers references for self-flowing transportation theories and technologies of cemented backfill materials.

     

/

返回文章
返回