摘要
针对低浓度全尾砂充填过程中的泌水造成输送堵管充填体强度不均匀和体积沉缩等问题,进行尾砂级配、胶凝材料用量、料浆浓度、固水材料掺量的正交实验,分析了各种因素对泌水率的影响,根据电阻率(ER)测试、SEM-EDS和XRD探讨了固水材料的作用机理。结果表明,充填料浆的泌水率随着尾砂细颗粒、胶砂比、浓度和固水材料掺量的增加而降低,料浆的浓度和固水材料掺量对泌水率的影响最显著。添加5%的固水材料可使充填材料泌水率降低10%,初始粘度降低30%,2 h粘度降低53%,28 d抗压强度提高20%。固水材料可改善充填材料的孔隙率,提高充填材料水化体系的SO42-浓度和pH值,生成钙矾石、斜方钙沸石以及C-S-H凝胶和硅铝酸盐凝胶的混合物,消耗大量自由水,高分子聚合物通过分子缠绕提高了体系的稳定性,改善了充填材料的泌水现象。
It is known that the bleeding phenomenon during the paste filling of the low concentration full tailings may result in the blocking of pipes,afterwards,the inhomogeneous distribution of strength and volume shrinkage of the filling body.For solving the above problems,orthogonal tests were designed for revealing the effect of tailing gradation,amount of binding material,slurry concentration and content of anti-bleeding material on bleeding rate by means of electrical resistivity test(ER),SEM-EDS and XRD.The results show that the bleeding rate of filling materials is inversely proportional to the tailing gradation,amount of binding material,slurry concentration and the content of anti-bleeding material.The concentration of slurry and the content of water solidifier had a great influence on the bleeding rate.By adding 5%anti-bleeding material equivalent to the total amount of glue-powder,the initial viscosity reduced by 30%,the 2 h viscosity reduced by 53%,the bleeding rate can be reduced by 10%and the 28 d compressive strength increased by 20%for the filling body.The anti-bleeding material improves the porosity of the,increases the concentration of SO42-and pH value of the hydration system of the filling body,as well as generates ettringite,trapezium,C-S-H gel and silicoaluminate gel,which consumed a lot of free water,improves system stability by entangling molecules so that improves the bleeding situation for the filling body.
作者
周在波
刘娟红
吴瑞东
吴爱祥
王洪江
王少勇
ZHOU Zaibo;LIU Juanhong;WU Ruidong;WU Aixiang;WANG Hongjiang;WANG Shaoyong(College of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of High-efficient Mining and Safety of Metal Mines,Ministry of Education,University of Science and Technology Beijing,Beijing 100083,China)
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2020年第7期481-488,共8页
Chinese Journal of Materials Research
基金
国家自然科学基金(51834001)。
关键词
复合材料
固水材料
正交实验
泌水率
微观机理
composite
anti-bleeding material
orthogonal tests
bleeding rate
microscopic mechanism
