铜尾矿改性水泥基地聚合物注浆材料性能与机理分析  

Performance and mechanism analysis of copper tailings modified cement-based geopolymer grouting materials

作　　者：付宏渊[1] 姚杰 邱祥 FU Hongyuan;YAO Jie;QIU Xiang(School of Traffic and Transportation Engineering,Changsha University of Science and Technology,Changsha 410114,China;School of Civil Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410114 [2]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《中南大学学报（自然科学版）》2024年第3期1107-1119,共13页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(52278439,51838001,52078066);湖南省科技创新计划项目(2023RC3138);湖南省自然科学基金面上资助项目(2023JJ30035);湖南省教育厅自然科学青年项目(21B0317);长沙理工大学专业学位研究生“实践创新与创业能力提升计划”项目(CLSJCX22004)。

摘　　要：为促进岩土工程绿色发展,提高尾矿资源化利用效率,选取铜尾矿制备铜尾矿改性水泥基地聚合物注浆材料,研究水固比、铜尾矿掺量、碱激发剂用量及碱激发剂模数对改性浆液各性能指标的影响规律及微观机理。研究结果表明:掺入尾矿有利于改善改性浆液力学性能,掺入碱激发剂能提高改性浆液整体的反应程度,减小改性浆液析水率;综合考虑各项性能指标,选取改性浆液最佳配比,即水固比为1.0,铜尾矿掺量为30%(质量分数,下同),碱激发剂用量为4%,碱激发剂模数为1.6;相较于纯水泥浆液,改性浆液最佳配比黏度减小11.1%,流动度增大22.3%,析水率减小29.7%,28 d结石体抗压强度仅减小9.5%,耐久性能良好;改性浆液发生地聚合物反应形成了具有三维空间网状结构的C-A-S-H凝胶和N-A-S-H凝胶等胶凝物质。本研究成果可为岩土工程提供高性能低成本的注浆材料,同时还将为尾矿等固废材料资源化利用提供参考。Copper tailings were chosen to prepare copper tailings modified cement-based geopolymer grouting materials in order to promote the green growth of geotechnical engineering and enhance the efficiency of resource exploitation of tailings.The effects of water-to-solid ratio,copper tailings doping,alkali activator doping and alkali activator modulus on the performance indicators and microscopic mechanisms of the modified slurry were investigated.The results show that adding tailings can improve the compressive strength of the modified slurry stone,and that adding alkali activator can improve the overall reaction degree of the slurry as well as reduce the water separation rate of the slurry.Taking into account the performance indicators,the optimal ratio of the modified slurry is selected as water-to-solid ratio 1.0,copper tailings doping 30%(mass fraction),alkali activator doping 4%,and alkali activator modulus 1.6.Compared with pure cement slurry,the optimum proportion viscosity of the modified slurry is reduced by 11.1%,the fluidity of the modified slurry is increased by 22.3%,the water separation rate of the modified slurry is reduced by 29.7%,and the 28 d compressive strength of the modified slurry stone is only reduced by 9.5%.The geopolymer reactions in the modified slurry result in the formation of three-dimensional network structures such as C-A-S-H gel and N-A-S-H gel,which have excellent performance.The findings of this study can provide high-performance and low-cost grouting materials for geotechnical engineering,as well as reference for resource exploitation of tailings and other solid waste materials.

关 键 词：岩土工程 注浆材料 铜尾矿 地聚合物 碱激发 微观机理 

分 类 号：U414[交通运输工程—道路与铁道工程]