| 摘要: |
| 采用轻质陶砂、水泥、偏高岭土和石灰石粉制备了石灰石-煅烧黏土-水泥（LC3）砂浆，研究了陶砂掺量及预湿状态对LC3砂浆干密度、力学性能、抗渗性能及抗氯离子侵蚀能力的影响，分析了其强度形成和微观结构机理. 结果表明：随着砂胶比的增大，LC3砂浆的干密度和抗压强度逐渐降低，累积吸水量逐渐增大，抗氯离子侵蚀能力逐渐增强；与掺未预湿陶砂的LC3砂浆相比，掺预湿陶砂的LC3砂浆试件28 d抗压强度增大3.4%~10.8%，28 d电通量降低59.0%~80.0%，累积吸水量降低更为显著. LC3体系中石灰石粉的成核作用能够促进水泥早期水化，偏高岭土的火山灰反应有利于细化孔结构，同时预湿陶砂的内养护效应能够维持基体内部湿度继续促进水泥水化，使得掺预湿陶砂的LC3砂浆微观结构更为密实，从而提高了其力学性能、抗渗性能和抗氯离子侵蚀能力. |
| 关键词: 陶砂 石灰石-煅烧黏土-水泥 力学性能 抗渗性能 孔结构 |
| DOI：10.3969/j.issn.1007-9629.2024.01.003 |
| 分类号:TU528.01 |
| 基金项目:国家自然科学基金资助项目（52208286）；湖北省自然科学基金资助项目（2022CFB672）；武汉知识创新专项-曙光计划项目（2022020801020362）；武汉工程大学科学研究基金资助项目（K2021031） |
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| Effect of Ceramsite Sand on Properties of Limestone-Calcined Clay-Cement Mortar |
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CHENG Shukai1,2, YOU Xiao1, CHEN Xuyong1,2, CHEN Kang1, WU Ziyang1
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1.Civil Engineering and Architecture， Wuhan Institute of Technology， Wuhan 430073， China;2.Hubei Provincial Engineering Research Center for Green Civil Engineering Materials and Structures， Wuhan Institute of Technology， Wuhan 430073， China
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| Abstract: |
| Limestone calcined clay cement （LC3） mortar was prepared by using light ceramsite sand， cement， metakaolin and limestone powder. The influences of ceramsite sand content and prewetting state on the dry density， mechanical properties， impermeability and resistance to chloride ion erosion of LC3 mortar were investigated and the strength formation and microstructure mechanism were analyzed. The results show that the dry density and compressive strength of LC3 mortar decrease gradually with the increases of the mass ratio of ceramic sand to binder. The cumulative water absorption of LC3 mortar increases， while its chloride ion penetration resistance increases. However， compared with LC3 mortar without prewet ceramic sand， the 28 d compressive strength of samples mixed with prewet ceramic sand increase by 3.4%-10.8%， the 28 d electric flux decrease by 59.0%-80.0%. In addition， the cumulative water absorption decreases more significantly. For the LC3 system， the nucleation of limestone powder promotes the early hydration of cement and the pozzolanic reaction of calcined clay is contributed to refining pore structure. Meanwhile， the internal humidity of the matrix and the hydration of cement is promoted because of internal curing effect of the prewet ceramic sand， which improves microstructure of the prewet ceramic sand LC3 mortar more dense， and thus its mechanical properties， impermeability and resistance to chloride ion erosion are enhanced. |
| Key words: ceramsite sand limestone-calcined clay-cement mechanical property impermeability pore structure |
