| 摘要: |
| 采用真密度分析仪、水化热法和X射线衍射（XRD）仪研究了2种聚醚类减缩剂（L SRA和S SRA）对新拌水泥浆体水化进程和体积变化的影响.结果表明：减缩剂对水泥早期水化进程有延缓作用；新拌水泥浆体体积变化过程中极速收缩期、收缩暂停期和收缩趋稳期的曲线规律与其水化放热速率曲线规律一致，快速收缩期体积变化曲线拐点所对应的时间与水化放热速率曲线放热峰值所对应的时间基本一致，2曲线存在相互对应的关联性，共同说明减缩剂对水泥浆体水化进程有延缓作用. |
| 关键词: 减缩剂 体积变化 水化进程 真密度分析仪 |
| DOI：10.3969/j.issn.1007 9629.2020.03.002 |
| 分类号: |
| 基金项目:“十三五”国家重点专项项目(2016YFC0701004);上海市科委项目（19DZ1201404,19DZ1202702）；上海市2019年度“联盟计划”资助项目（LM201947）；国家自然科学基金资助项目(51678441);上海市经信委专项资金项目（沪CXY 2016 012）;上海市建委专项课题（住建管2017 001 009） |
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| Effect of Shrinkage Reducing Agents on Absolute VolumeChange of Fresh Cement Paste |
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LI Biyun, SUN Zhenping, HU Kuangyi, YANG Xu
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School of Materials Science and Engineering, Tongji University, Shanghai 201804, China
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| Abstract: |
| Effects of two types of polyether shrinkage reducing agent(L SRA and S SRA) on hydration process and absolute volume change of fresh cement paste were investigated using helium pycnometer, hydration heat and X ray diffraction（XRD）. The results show that hydration process of cement paste in early age is retarded by the shrinkage reducing agents. Curves of flash shrinkage stage, shrinkage suspension stage, and shrinkage slowdown stage are in good agreement with heat flow. Time of the inflection point during fast shrinkage stage is consistent with the time of heat flow peak. There exists a mutually corresponding relationship between absolute volume change and heat flow, which explains the delay effect of shrinkage reducing agent on hydration of cement paste. |
| Key words: shrinkage reducing agent absolute volume change hydration process helium pycnometer |
