| 摘要: |
以电石渣、脱硫石膏和钢渣掺量为影响因素，改性粉煤灰地聚物7、28 d抗压强度为响应值，使用响应面法（RSM）研究各种固体废弃物的交互作用对改性粉煤灰地聚物强度的影响规律，并通过水化热、扫描电镜（SEM）和X射线衍射（XRD）分析其增强机理.结果表明：经RSM优化设计后的电石渣、脱硫石膏和钢渣的最佳掺量分别为6.34%、1.60%和29.47%，改性粉煤灰地聚物7、28 d抗压强度分别达到18.10、29.92 MPa；电石渣和钢渣通过增强体系碱性，加快Si和Al的溶解，促进水化硅铝酸钙（钠）的生成，提高改性粉煤灰地聚物各龄期的强度；脱硫石膏通过提高Ca2+和SO42-![]() ![]() 含量，生成钙矾石晶体，提高改性粉煤灰地聚物的早期强度；随着养护龄期的延长，改性粉煤灰地聚物中凝胶逐渐增多，可填充微小孔隙，使结构变得更加密实，因此强度得到提高. |
| 关键词: 粉煤灰地聚物 电石渣-脱硫石膏-钢渣 响应面法 增强机理 |
| DOI：10.3969/j.issn.1007-9629.2023.08.007 |
| 分类号:TU526;U414 |
| 基金项目:国家自然科学基金资助项目（52278239，51978080）；湖南省科技厅重点研发项目（2021SK2044）；湖南省研究生创新项目（QL20220194） |
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| Synergistic Enhancement Mechanism of Calcium Carbide Residue-Desulfurization Gypsum-Steel Slag Modified Fly Ash Geopolymer |
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GAO Yingli, ZHU Zhanghuang, MENG Hao, HU Xinlang, LI Zhengkang
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School of Traffic and Transportation Engineering， Changsha University of Science & Technology， Changsha 410114， China
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| Abstract: |
Taking the contents of calcium carbide residue， desulfurization gypsum and steel slag as the influencing factors， and the compressive strengths of modified fly ash geopolymer at 7 and 28 d as the response values， the response surface method （RSM） was used to study the influence of each solid waste interaction on the strength of modified fly ash geopolymer. The enhancement mechanism was analyzed by hydration heat， scanning electron microscope（SEM） and X-ray diffraction（XRD）. The results show that the optimal contents of calcium carbide residue， desulfurization gypsum and steel slag after optimizing design by RSM are 6.34%， 1.60% and 29.47% respectively， and the compressive strength of modified fly ash geopolymer at 7 and 28 d reaches 18.10 and 29.92 MPa respectively. Calcium carbide residue and steel slag improve the strength of modified fly ash geopolymer at each age by increasing the alkalinity of the system， which accelerating the dissolution of Si and Al， and promoting the generation of calcium（sodium） aluminosilicate hydrate. Desulfurization gypsum improves the early strength of modified fly ash geopolymer by increasing the contents of Ca2+ and SO42-![]() ![]() to generate ettringite crystals. With increasing curing age， modified fly ash geopolymer gradually produces more gel， which filling in the microscopic pores and improving the structure density， and hence improving the strength. |
| Key words: fly ash geopolymer calcium carbide residue-desulfurization gypsum-steel slag response surface method enhancement mechanism |
