| 摘要: |
| 采用80 ℃下恒温12 h的蒸养制度对砂浆进行了蒸养，蒸养结束后采用自然养护、水养和标养3种方式进行后续养护，同时设置了全程标养砂浆作为对照组.研究了不同养护制度下砂浆的早期强度发展规律，并基于X射线计算机断层扫描（X-CT）技术对砂浆的孔结构特征进行了分析.结果表明：80 ℃下恒温12 h蒸养使砂浆孔隙率增大，最终导致蒸养砂浆28 d抗压强度低于全程标养砂浆；蒸养砂浆抗压强度随孔隙率增大而快速降低，两者之间呈现良好的线性关系；蒸养后水养和标养可以有效降低蒸养砂浆的孔隙率，使其28 d抗压强度高于蒸养后自然养护的砂浆；砂浆孔隙的孔体积与球形度存在明显的负相关关系，且蒸养会使孔体积-球形度分布规律中的异常值增多. |
| 关键词: 蒸养 X射线计算机断层扫描 活动轮廓模型 孔结构 球形度 |
| DOI：10.3969/j.issn.1007-9629.2022.09.001 |
| 分类号:TU528.01 |
| 基金项目:国家自然科学基金资助项目（51979090）；中央高校基本科研业务费专项资金资助项目（B200202076） |
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| Pore Structure of Steam Cured High Volume Mineral Admixture Mortar Based on X-CT Technology |
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GUO Yuzhu1, CHEN Xudong1, NING Yingjie2, CHEN Yuzhi3
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1.College of Civil and Transportation Engineering， Hohai University， Nanjing 210098， China;2.Zhejiang Communications Construction Group Co.， Ltd.， Hangzhou 310051， China;3.Architecture Engineering Institute， Jinling Institute of Technology， Nanjing 211169， China
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| Abstract: |
| The mortar was steam cured using a constant temperature of 80 ℃ for 12 h steam curing system. After the completion of steam curing， three types of subsequent curing were used： natural curing， water curing and standard curing， while the whole standard cured mortar was set as a comparison group. The early strength development patterns of mortars under different curing regimes were studied， and the pore structure characteristics of mortar were analyzed based on X-ray computed tomography （X-CT） technique. The results show that steam curing at a constant temperature of 80 ℃ for 12 h increases the porosity of the mortar， which eventually leads to a lower 28 d compressive strength of the steam cured mortar than that of the whole standard cured mortar. The compressive strength of the steam cured mortar decreases rapidly with the increase of porosity， and a good linear relationship is shown between them. The water curing and standard curing after steam curing can effectively reduce the porosity of the steam cured mortar and make its 28 d compressive strength higher than that of the mortar naturally cured after steam curing. In addition， there is an obviously negative correlation between the pore volume and sphericity of mortar pores， and the steam curing system will increase the outliers in this distribution law of pore volume-sphericity. |
| Key words: steam curing X-ray computed tomography active contour model pore structure sphericity |
