Study on the mechanical properties and hydration mechanism of alkali activated copper slag fly ash composite cementitious material
Li Bowen;Cheng Yunhai;Li Weili;Wang Yong;Zhou Yuncong
旨在探讨利用碱激发剂制备铜渣-粉煤灰复合胶凝材料的可行性及其性能表现。选择铜渣和粉煤灰作为主要原料,通过实验确定其最佳配比和激发剂种类及浓度,发现以7.5%的水玻璃为激发剂时,材料的力学性能最佳。过量的碱激发剂会导致返碱现象、增加与模具的粘合度及拆模困难,甚至降低成品强度,因此在生产过程中需严格控制激发剂的掺量。通过实验分析不同变量对材料性能的影响,包括原材料细度、激发剂浓度、养护条件等,确定了优化的制备工艺。实验结果表明,优化后的复合材料在28 d内的强度可达71 MPa,显著优于普通硅酸盐水泥。在早期强度发展迅速的同时,后期强度虽然增长缓慢,但整体性能依然优越。这种表现为其在实际工程应用中提供了理论依据和实践支持。结合微观结构分析和实际应用研究,揭示了硅铝酸盐凝胶的形成机制,进一步优化了配方和工艺。研究结果证明,该材料具有显著的环保效益和经济潜力。其广泛的应用前景不仅可以部分替代传统水泥,还能实现工业废弃物的高效资源化利用,推动建筑行业的可持续发展。通过不断优化技术和降低成本,碱激发铜渣-粉煤灰复合胶凝材料将在绿色建筑和环保材料领域发挥更大的作用。
In order to explore the feasibility and performance of using alkaline activators to prepare copper slag fly ash composite cementitious materials, copper slag and fly ash were selected as the main raw materials, and the optimal ratio, activator type and concentration were determined through experiments. It was found that the mechanical properties of the material were optimal when 7.5% sodium silicate was used as the activator. Excessive alkaline activator can lead to alkalization, increased adhesion with the mold, difficulty in demolding, and even decrease the strength of the finished product. Therefore, strict control of the dosage of activator is necessary in the production process. Through experimental analysis of the effects of different variables on material properties, including raw material fineness, activator concentration, curing conditions, etc., the optimized preparation process was determined. The experimental results show that the optimized composite material has a strength of 71 MPa within 28 days, which is significantly better than ordinary Portland cement. While early strength development is rapid, later strength growth is slow, but overall performance is still superior. It was provided that theoretical basis and practical support for its practical engineering applications.In this paper, the formation mechanism of aluminosilicate gel was revealed and the formula and process were further optimized by combining microstructure analysis and practical application research. The research results have shown that this material has significant environmental benefits and economic potential. Its broad application prospects not only partially replace traditional cement, but also achieve efficient resource utilization of industrial waste, promoting sustainable development of the construction industry. By continuously optimizing technology and reducing costs, alkali activated copper slag fly ash composite cementitious materials will play a greater role in the fields of green buildings and environmentally friendly materials.
copper slag;fly ash;alkali activator;water glass;composite cementitious materials;resource utilization
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会