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通过水热合成法制备了不同Ca/Si比的水化硅酸钙(C-S-H)，并在6 mol/LNH4Cl溶液中加速脱钙，对不同Ca/Si比C-S-H脱钙前后的化学成分、链结构和微观结构进行分析。结果表明：C-S-H为不规则团聚体形成的凝胶结构。随着Ca/Si比增加，C-S-H中的二聚体和链端基团含量增加，平均聚合度和平均链长减小。脱钙后，C-S-H结构发生解体，硅酸盐链相互交联形成三维网状结构的硅胶，导致C-S-H失去其胶凝性能。
Abstract：This paper was to synthesize C-S-H with different Ca/Si ratios by a hydrothermal synthesis method, and decalcify it using 6 mol/L NH4Cl solutions. The chemical composition, chain structure and microstructure were analyzed. The results show that C-S-H is a gel structure formed by irregular aggregates. The content of dimer and chain end groups in C-S-H increases, while the average degree of polymerization and average chain length decreases with the increase of Ca/Si ratio. The change of C-S-H structure includes decreased interlayer distance, cross-linked silicate chains, and amorphous silica gels formed after decalcification, resulting in the loss of C-S-H cohesion.
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基本信息:
DOI：10.14062/j.issn.0454-5648.20230319
中图分类号:TU528
引用信息:
[1]张紫薇,刘振陶,李国新.钙硅比对水化硅酸钙脱钙过程的影响及机理[J].硅酸盐学报,2023,51(11):2924-2930.DOI:10.14062/j.issn.0454-5648.20230319.
基金信息:
陕西省交通运输厅科研项目(19-19K)
2023-05-11
2023
2023-09-21
2023-09-19
2023
1
2023-08-14
2023-08-14
2023-08-14