碳化作用对镁质胶凝材料微观结构演变过程的影响
收稿日期: 2021-10-13
网络出版日期: 2022-06-22
基金资助
青海省应用基础研究项目(2021-ZJ-737);青海省重点研发与转化计划项目(2019-GX-165)
Effect of carbonization on evolution process of microstructure of magnesium oxychloride cement
Received date: 2021-10-13
Online published: 2022-06-22
为揭示碳化作用对镁质胶凝材料微观结构演变过程的影响，通过扫描电镜（SEM）、X射线衍射（XRD）和压力试验机，对室内养护5 a龄期的镁质胶凝材料净浆试样和30 a龄期的镁质胶凝材料房梁试样进行分析。结果表明，碳化作用对镁质胶凝材料的微观形貌和物相组成影响较大。空气中的二氧化碳由表及里渗入镁质胶凝材料中，在二氧化碳渗入的过程中引起镁质胶凝材料微观形貌和物相组成的变化。镁质胶凝材料的微观形貌主要由针棒状、多孔状向块状转变，物相由5·1·8［5Mg（OH）2·MgCl2·8H2O］相经2·1·1·6［2MgCO3·Mg（OH）2·MgCl2·6H2O］相最终转化为稳定的水菱镁矿和菱镁矿。由于碳化作用，镁质胶凝材料5 a龄期的抗压强度相比1 a龄期下降了22.1 MPa。因此，需要采用隔离方法处理镁质胶凝材料，以减少其碳化作用，延长其使用年限。
常成功 , 文静 , 董金美 , 郑卫新 , 阎峰云 , 肖学英 . 碳化作用对镁质胶凝材料微观结构演变过程的影响[J]. 无机盐工业, 2022 , 54(6) : 61 -65 . DOI: 10.19964/j.issn.1006-4990.2021-0546
To reveal the effect of carbonization on the evolution process of the microstructure of magnesium oxychloride cement，scanning electron microscope（SEM），X-ray diffraction（XRD） and pressure testing machines were used to analyze the pure slurry and roof beam of magnesium oxychloride cement which were cured for 5 years and 30 years in the indoor environment，respectively.The results showed that carbonization exhibited an obvious influence on the microscopic morphology and phase composition of magnesium oxychloride cement.The CO2 in the air penetrated into magnesium oxychloride cement from the surface to the inside，resulting in the change of the microscopic morphology and phase composition of magnesium oxychloride cement.The morphology of magnesium oxychloride cement was transformed mainly from needle，porous to block shape，meanwhile its phase composition also changed from 5·1·8［5Mg（OH）2·MgCl2·8H2O］ to 2·1·1·6［2MgCO3·Mg（OH）2·MgCl2·6H2O］ phase，and finally to the stable hydromagnesite and magnesite.Owing to carbonization，the compressive strength of magnesium oxychloride cement cured for 5 years decreased by 22.1 MPa compared with that maintained for 1 year.Therefore，it was necessary to use an isolation method to treat magnesium oxychloride cement to reduce carbonization and extend its service life.
| 1 | CHANG Chenggong， DONG Jinmei， XIAO Xueying，et al.Long?term mechanical properties and micro mechanism of magnesium oxychloride cement concrete［J］.Advances in Cement Research，2020，32（8）：371-378. |
| 2 | 中国科学院青海盐湖研究所.中国科学院盐湖研究六十年［M］.北京：科学出版社，2015. |
| 2 | Qinghai Institute of Salt Lakes，Chinese Academy of Sciences.Sixty years of research on salt lakes by the Chinese Academy of Sciences［M］.Beijing：Science Press，2015. |
| 3 | 岳涛，朱黎霞，杨荣榛，等.无机镁盐晶须的应用研究进展［J］.无机盐工业，2003，35（4）：11-13. |
| 3 | YUE Tao， ZHU Lixia， YANG Rongzhen，et al.Advances in the application of inorganic magnesium salt whiskers［J］.Inorganic Che? |
| 3 | Industry micals，2003，35（4）：11-13. |
| 4 | LI Ke， WANG Yuansheng， YAO Nina，et al.Recent progress of magnesium oxychloride cement：Manufacture，curing，structure and performance［J］.Construction and Building Materials，2020，255.Doi：10.1016/j.conbuildmat.2020.119381 . |
| 5 | GUO Yingying， ZHANG Yixia，SOE K，et al.Recent development in magnesium oxychloride cement［J］.Structural Concrete，2018，19（5）：1290-1300. |
| 6 | 杨红健，马学景，何豫基，等.氧化钙对氯氧镁水泥低温凝结性能的影响［J］.无机盐工业，2015，47（4）：33-35. |
| 6 | YANG Hongjian， MA Xuejing， HE Yuji，et al.Effect of CaO on ma? |
| 6 | gnesium oxychloride cement setting performance at low temperature［J］.Inorganic Chemicals Industry，2015，47（4）：33-35. |
| 7 | CHEN Xiaoyang， ZHANG Tingting， BI Wanli，et al.Effect of tartaric acid and phosphoric acid on the water resistance of magnesium oxychloride（MOC） cement［J］.Construction and Building Ma? terials，2019，213：528-536. |
| 8 | HE Pingping， POON C S， TSANG D C W.Comparison of glass po? |
| 8 | wder and pulverized fuel ash for improving the water resistance of magnesium oxychloride cement［J］.Cement and Concrete Composites，2018，86：98-109. |
| 9 | HUANG Tingjie， YUAN Qiang， DENG Dehua.The role of phosphoric acid in improving the strength of magnesium oxychloride cement pastes with large molar ratios of H2O/MgCl2 ［J］.Cement and Concrete Composites，2019，97：379-386. |
| 10 | HE Pingping， POON C S， TSANG D C W.Using incinerated sewage sludge ash to improve the water resistance of magnesium oxychloride cement（MOC）［J］.Construction and Building Materials，2017，147：519-524. |
| 11 | YU Kequan， GUO Yingying， ZHANG Y X，et al.Magnesium oxychloride cement?based strain?hardening cementitious composite：Mechanical property and water resistance［J］.Construction and Building Materials，2020，261.Doi：10.1016/j.conbuildmat.2020 . |
| 11 | 119970. |
| 12 | GUO Yingying， ZHANG Yixia，SOE K，et al.Effect of fly ash on mechanical properties of magnesium oxychloride cement under water attack［J］.Structural Concrete，2020，21（3）：1181-1199. |
| 13 | HE Pingping， POON C S， TSANG D C W.Effect of pulverized fuel ash and CO2 curing on the water resistance of magnesium oxy? |
| 13 | chloride cement（MOC）［J］.Cement and Concrete Research，2017， 97：115-122. |
| 14 | GóCHEZ R， VREELAND T， WAMBAUGH J，et al.Conversion of magnesium oxychloride to chlorartinite and resulting increased |
| 14 | water resistance［J］.Materials Letters，2017，207：1-3. |
| 15 | POWER I M， DIPPLE G M， FRANCIS P S.Assessing the carbon sequestration potential of magnesium oxychloride cement building materials［J］.Cement and Concrete Composites，2017，78：97-107. |
| 16 | 张振禹，戴长禄，张铨昌，等.相5和相3的形成机理研究［J］.中国科学：B辑，1991，21（1）：82-89. |
| 16 | ZHANG Zhenyu， DAI Changlu， ZHANG Quanchang，et al.Study on formation mechanism of phase 5 and phase 3［J］.Science in China：SerB，1991，21（1）：82-89. |
/
| 〈 |
|
〉 |
