Effect of amorphous aluminum hydroxide on the phosphogypsum-based cementitious materials in prefabricated building field
Effect of amorphous aluminum hydroxide on the phosphogypsum-based cementitious materials in prefabricated building field
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DOI：
10.1016/j.jobe.2023.107437
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发表时间：
2023-07
影响因子：
6.4
通讯作者：
Pian Chen;B. Ma;H. Tan
中科院分区：
文献类型：
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作者：
Pian Chen;B. Ma;H. Tan
石膏基轻质板由于其独特的优点，如低成本和节能，良好的吸湿性，良好的居住性和耐火性，越来越多地应用于装配式建筑。目前，如何在生产过程中优化性能，加快固化速度，提高生产效率是需要研究的问题。研究了无定形氢氧化铝（A-AH）对磷石膏基固体废弃物胶凝材料力学性能、水化产物和体积稳定性的影响。在β-半水磷石膏（β-HPG）、高炉矿渣（BFS）和钢渣（SS）组成的三元体系中，制备了A-AH含量为0-4%的膏体。结果表明，A-AH的加入能促进β-HPG-BFS-SS（HBS）体系快速、稳定固化，通过促进AFt的早期生成提高早期强度，并促进C-A-S-H凝胶的形成。特别是当A-AH含量为1%时，可以提高HBS的早期和后期力学性能，改善体积稳定性，促进硅酸盐的水化程度，增加AFt和C-（A）-S-H凝胶的生成，提高C-（A）-S-H凝胶的聚合度。采用XRD、TG-DTG、27 Al-NMR、FTIR和29 Si-NMR等方法对水化产物进行了分析。通过水化热和pH值分析评价了水化过程。利用SEM-EDS和孔结构分析对水化产物的形貌和结构进行了表征。详细分析了A-AH对体系的作用机理。研究结论为三元体系HBS在装配式建筑领域的更好应用提供了参考和借鉴。
Gypsum-based lightweight panels are increasingly used in prefabricated buildings due to their unique advantages, such as low cost and energy saving, good moisture absorption, good habitability, and fire resistance. At present, how to optimize performance, accelerate curing speed and improve production efficiency in the production process are the problems that need to be studied. In this research, the influence of amorphous aluminum hydroxide (A-AH) on the phosphogypsum-based solid waste cementitious material, including the mechanical properties, hydration products, and volume stability, were investigated. Pastes with 0–4% content of A-AH in the ternary system consisting of β-hemihydrate phosphogypsum (β-HPG), ground blast-furnace slag (BFS) and steel slag (SS) were made. Results showed that the addition of A-AH could promote the rapid and stable curing of the β-HPG-BFS-SS (HBS) system, increase the early strength by accelerating the early generation of AFt, and promote the formation of C-A-S-H gel. Specially, 1% content of A-AH could enhance both the early and late mechanical property, improve the volume stability, promote the hydration degree of silicates and increase the generation of AFt and C-(A)-S-H gels, and increase the polymerization degree of C-(A)-S-H gel in HBS. Analyses of hydration products were based on XRD, TG-DTG,27Al-NMR, FTIR and29Si-NMR. Hydration process was evaluated by hydration heat and pH value analysis. The morphology and structure of hydration products were characterized by SEM-EDS and pore structure, respectively. The mechanism of A-AH acting on the system was analyzed in detail. The conclusions paved a new way to provide reference and insight for the better application of ternary system HBS in prefabricated building field.