| 摘要: |
| 对比轻烧MgO，对水泥硬化浆体的膨胀和抗压强度随纳米MgO掺量的变化规律进行研究.结果表明：经压蒸安定性试验后，在浆体中的纳米MgO和轻烧MgO均已水化，其体积安定性合格的最大掺量（质量分数）分别约为10%和4%；在40℃水中养护至730d时，纳米MgO和轻烧MgO均已水化；水泥硬化浆体膨胀率随MgO掺量和养护时间的增加而增加，掺纳米MgO浆体的膨胀较易趋于稳定；水泥硬化浆体抗压强度随纳米MgO掺量的增加而增大，随轻烧MgO掺量的增加而降低.纳米MgO具有较高的安定性掺量和较好的强度稳定性，其膨胀可用于补偿大体积混凝土的收缩. |
| 关键词: 水泥硬化浆体 纳米MgO 轻烧MgO 膨胀 强度 |
| DOI：103969/j.issn.1007 9629201705018 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51778582）；浙江省科技厅公益项目（2016C31009）；住建部2014年科学技术项目（2014 K4 011） |
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| Effects of Nano MgO on Expansion and Strength of Hardened Cement Pastes |
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YE Qing1, YU Shenghua1, ZHANG Zenan2, ZHANG Qiang3, SHI Tao1
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1.College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China;2.College of Physics, Zhejiang University of Technology, Hangzhou 310014, China;3.Shaoxing Huaguan New Building Materials Co., Ltd., Shaoxing 312000, China
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| Abstract: |
| The variation of expansion and compressive strength of hardened cement paste with nano MgO added was studied compared with that for light burnt MgO. Results indicate that nano MgO and light burnt MgO in the paste are hydrated after the test of cement autoclave soundness, and their qualified maximum for soundness is about 10% and 4%(by mass) respectively. Cured in water at 40℃ till 730days, both nano MgO and light burnt MgO in pastes are hydrated, paste expansions increase with the increase of MgO and curing time, and the paste expansion added with nano MgO tend to be stable more easily than that with light burnt MgO. Meanwhile, the paste compressive strengths increase with the increase of nano MgO， but decrease with the increase of light burnt MgO. For cement based materials, nano MgO has advantages of higher soundness and higher stability for strength as compared with light burnt MgO. The results suggest that expansions from nano MgO hydration may be used to compensate the shrinkage of mass concrete. |
| Key words: hardened cement paste nano MgO light burnt MgO expansion strength |
