吉林建筑大学学报

聚焦于以碱激发矿渣-粉煤灰复合体系构建绿色胶凝材料应对传统硅酸盐水泥高能耗与高碳排放的问题，通过调控硅酸钠和氢氧化钠用量，系统研究不同硅铝比（Si/Al）与钠铝比（Na/Al）对其无侧限抗压强度（UCS）的影响。结果表明，在Na/Al恒定的条件下，Si/Al由3.0升高至3.4将导致UCS显著降低，主要归因于过量硅源难以反应及凝胶交联度下降；而在Si/Al固定时，Na/Al由1.1降至0.8则因碱度不足限制铝源溶解及凝胶生成，也使得UCS下降。SEM与XRD表征显示，Si/Al=3.0与Na/Al=1.1组合下可形成致密的C—A—S—H与N—A—S—H凝胶网络，对应最佳力学性能，但伴随泛碱与干缩开裂问题。进一步以钢渣和电石渣部分替代化学碱源虽可缓解泛碱现象，但因碱度不足，7 d UCS降至3.4 MPa，力学性能明显衰减。该研究系统揭示了Si/Al与Na/Al比对地聚物性能的协同调控机制，并探讨了碱性固废的激发潜力，为地聚物配比优化及工业固废资源化利用提供理论依据。

Focused on constructing green cementitious materials using an alkali-activated slag-fly ash composite system to address the issues of high energy consumption and high carbon emissions of traditional Portland cement. By regulating the dosages of sodium silicate and sodium hydroxide, the effects of different siliconaluminum ratios(Si/Al) and sodium-aluminum ratios(Na/Al) on its unconfined compressive strength(UCS) were systematically studied. The results show that under the condition of constant Na/Al, an increase in Si/Al from 3.0 to 3.4 will lead to a significant decrease in UCS, mainly attributed to the difficulty of reaction of excessive silicon source and the decrease in gel crosslinking degree. When Si/Al is fixed, if Na/Al drops from 1.1 to 0.8, the insufficient alkalinity limits the dissolution of the aluminum source and the formation of gel, which also leads to a decrease in UCS. SEM and XRD characterizations show that under the combination of Si/Al=3.0 and Na/Al=1.1, a dense gel network of C—A—S—H and N—A—S—H can be formed, corresponding to the best mechanical properties, but accompanied by alkali effsification and dry shrinkage cracking problems. Although partially replacing the chemical alkali source with steel slag and calcium carbide slag can alleviate the efflorescence phenomenon, due to insufficient alkalinity, the 7 d UCS drops to 3.4 MPa, and the mechanical properties decline significantly. This study systematically revealed the synergistic regulatory mechanism of the geopolymer performance by Si/Al and Na/Al ratios, and explored the activation potential of alkaline solid waste, providing a theoretical basis for the optimizationof geopolymer ratios and the resource utilization of industrial solid waste.