| 摘要: |
| 通过微生物矿化技术提升赤泥的碱激发反应，研究了矿化微生物用量、Ca（OH）2用量和尿素浓度对赤泥基碱激发胶凝材料强度的影响；通过扫描电镜（SEM）、X射线衍射仪（XRD）等分析了矿化微生物作用下碱激发胶凝材料的物相变化与微观形貌，并对矿化微生物改性赤泥基碱激发胶凝材料机理进行分析.结果表明：微生物矿化作用可以促进赤泥的碱激发反应，生成更多的胶凝物质，增加体系密实度，从而提高赤泥基碱激发胶凝材料的强度；赤泥基碱激发胶凝材料的强度随矿化微生物用量、尿素浓度及养护龄期的增加而增大；当加入1.5 mol/L尿素和75 mL矿化微生物时，赤泥强度增加最为显著，相较仅加入等量Ca（OH）2的工况，提升幅度可达85.7%；与此同时，微生物矿化作用还显著加快了胶凝材料强度的增长速率，有利于胶凝材料早期强度的形成. |
| 关键词: 赤泥 碱激发 微生物矿化 道路工程 微观结构 |
| DOI：10.3969/j.issn.1007-9629.2024.01.002 |
| 分类号:TU525 |
| 基金项目:国家自然科学基金资助项目（51809139） |
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| Enhancement of Properties of Alkali-Activated Red Mud Based Cementitious Materials by Mineralizing Microbe |
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ZHANG Xingwu1, LIU Peng1, CHENG Yu2
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1.School of Civil Engineering， Nanjing Forestry University， Nanjing 210037， China;2.School of Transportation， Shandong University of Science and Technology， Qingdao 266510， China
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| Abstract: |
| It was proposed to improve the alkali-activated reaction of red mud through microbial mineralization technology， and the effects of mineralizing microbe amount ，Ca（OH）2 content and urea concentration on the strength of red mud-activated cementitious materials was investigated. The change of material composition and microscopic morphology of alkali-activated cementitious material under the action of mineralizing microbe were also analyzed by means of scanning electron microscope （ SEM ） and X-ray diffraction （ XRD）， and the mechanism of cementitious material modified by mineralizing microbe was obtained. The results show that microbial mineralization can promote the alkali-activated reaction of red mud to produce more cementitious material and increase the system compactness， thus the strength of red mud-activated cementitious materials is improved. And the strength can increase with increasing the mineralizing microbe amount， the urea concentration， and the curing age. When 1.5 mol/L urea and 75 mL mineralizing microbe after centrifugation are added， the strength of red mud increases most significantly. Compared to the sample with only calcium hydroxide added， the increase in strength can reach 85 .7%. At the same time， the formation of cementitious materials is significantly accelerated by microbial mineralization， which is conducive to the formation of early strength of cementitious materials. |
| Key words: red mud alkali-activated microbial mineralization road engineering microstructure |
