| 摘要: |
| 为了研究碳化过程中水化硅酸钙凝胶（C S H）平均链长的演变规律，采用29Si NMR技术对不同水灰比、不同碳化时间的水泥净浆试样进行了分析.同时，对碳化后试样的氢氧化钙（CH）和CaCO3质量进行了热重分析.结果表明：加速碳化条件下试样的C S H平均链长增加，相同水灰比试样的碳化时间越长，其C S H平均链长越长；相同碳化时间的试样，水灰比越大，其C S H平均链长越长；碳化28d之后，053水灰比（质量比，下同）试样的C S H已基本完全碳化，035水灰比试样的C S H结构在一定程度上发生了变化，而023水灰比试样的C S H结构基本没有变化.另外，053水灰比试样的C S H碳化不是在CH完全反应后才开始的，碳化至7d时CH和C S H都发生了碳化反应且都没有完全碳化. |
| 关键词: 水化硅酸钙凝胶（C S H） 核磁共振 碳化 |
| DOI：103969/j.issn1007 9629201603003 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51178103） |
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| Evolution Law of Average Chain Length of C S H during the Carbonation Process |
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PAN Ganghua, BAO Bingfeng, WANG Yudong
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College of Materials Science and Engineering, Southeast University, Nanjing 211189, China
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| Abstract: |
| In order to study the evolution law of calcium silicate hydrate gel(C S H) average chain length during the carbonation process, the cement paste specimens prepared from different water cement ratios (mw/mc) and carbonation ages were studied by using the nuclear magnetic resonance(NMR) spectroscopy. Meanwhile, the content of calcium hydroxide(CH) and CaCO3 was calculated by thermogravimetric experiment. The experimental results show that the C S H average chain length changes from low to high under the condition of accelerated carbonation. For the same mw/mc specimen, its C S H average chain length increases with the extension of carbonation age. After 28 days carbonation, 053mw/mc specimens C S H is almost completely carbonated and 035mw/mc specimens C S H structure changes to certain extent, while 023mw/mc specimen changes barely. In addition, the carbonation of 053mw/mc specimens C S H does not begin with CH completely reacted; after 7 days of carbonation both CH and C S H undergoes carbonation reaction but the carbonation is not completed. |
| Key words: calcium silicate hydrate gel(C S H) nuclear magnetic resonance（NMR） carbonation |
