复合碱激发下粉煤灰基地质聚合物的结构重构与性能优化

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中图分类号：TQ172 文献标志码：A 文章编号：1671-0460（2026）01-0121-07

Abstract： In order to realize the high-value utilization and low-carbon conversion ofbulk solid wastes such as fly ash， in this paper， fly ash from Dalian Zhuanghe Power Plant was used as the main raw material，and NaOH- ⋅Na2SiO3 composite alkali-activatedsystem was used to prepare flyash based geopolymer （FAG）atroom temperature.The effects of alkalinity dosage Na2O mass fraction， the same below）， modulus and water-binder mass ratio on gel structure and mechanical properties weresystematicallyinvestigated.Theresultsshowed that thecomposite alkalisystem significantlyimproved theactivationdegre and gelationefficiencyofflyash，and promotedthe formationandskeleton densification of N-A-S-H/C-A-S-H gel. When doping amount was 8% ，the mass ratio of sodium silicate to sodium hydroxide was1.0，andthe water-bindermass ratiowas0.28，the14dcompressivestrengthofthesample reached43.638 MPa ，whichwasabout 80% higher than that of the single alkali system. The results of XRD，FTIR and TG/DTG showed that theflyash glass phase was effectivelydissolvedand reconstructed in the composite alkali system，and Si—O—T [T=Si Al） bonds were rearranged to formanamorphous gel network dominated byN-A-S-H.Thereaction mechanism analysisresultsshowed that NaOH dominated the dissolution process and Na2SiO3 dominated the polycondensation process.The synergistic effect ofthe two made the disolution and polymerization rates match，which significantly improved the structural compactness and mechanical properties.

Key words： Fly ash; Geopolymers; Compound alkali excitation; N-A-S-H gel; Reaction mechanism

粉煤灰（FA）是燃煤电厂排放量最大的固体废弃物之一，长期堆存不仅占用土地资源，还可能引发重金属淋溶与环境污染问题[1-2]。（剩余10091字）