偏高岭土单掺及复掺对混凝土体积稳定性的影响  

Effect of Single and Compound Blending of Metakaolin on Volumetric Stability of Concrete

作　　者：陈祖军 李世华 郑倩 梁丽敏 CHEN Zujun;LI Shihua;ZHENG Qian;LIANG Limin(Yunnan Construction Investment Holding Group Co.,Ltd.,Kunming 650501,Yunnan,China;Yunnan Construction Investment Holding Green and High Performance Concrete Co.,Ltd.,Kunming 650501,Yunnan,China;Yunnan Engineering Research Center of High Performance Concrete,Kunming 650501,Yunnan,China)

机构地区：[1]云南建设投资控股集团有限公司,云南昆明650501 [2]云南建投绿色高性能混凝土股份有限公司,云南昆明650501 [3]云南省高性能混凝土工程研究中心,云南昆明650501

出　　处：《建筑施工》2023年第7期1476-1479,共4页Building Construction

基　　金：云南省住房和城乡建设厅科研开发项目(K027593986)。

摘　　要：为改善混凝土体积稳定性,研究了偏高岭土单掺以及其与粉煤灰、矿渣粉复掺对混凝土补偿收缩性能、早期收缩性能及早期抗裂性能的影响。试验结果表明,掺入偏高岭土能有效降低混凝土的收缩率,改善混凝土后期的抗收缩性能,偏高岭土单掺时,最佳掺量为10%。偏高岭土与粉煤灰、矿渣粉进行复合优化可以发挥叠加效应,有效降低体系的收缩。在偏高岭土掺量和掺合料取代水泥量固定不变时,混凝土初凝后的收缩率随粉煤灰掺量的增加而降低,抗裂性能随着粉煤灰掺量的增加而提高。相关结论可为工程中的具体应用提供参考。In order to improve the volume stability of concrete,the effects of single admixture of kaolinite and its compounding with fly ash and slag powder on the compensatory shrinkage performance,early shrinkage performance and early crack resistance of concrete were studied.The test results showed that the incorporation of metakaolin could effectively reduce the shrinkage of concrete and improve the shrinkage resistance of concrete in the later stage,and the optimum amount of metakaolin was 10%when it was blended alone.The compound optimization of metakaolin with fly ash and slag powder can play a superposition effect and effectively reduce the shrinkage of the system.The shrinkage of concrete after initial setting decreases with the increase of fly ash admixture and the anti-cracking property increases with the increase of fly ash admixture when the amount of kaolin and the amount of cement replaced by admixture are fixed.The relevant conclusions can provide references for specific applications in engineering.

关 键 词：偏高岭土 体积稳定性 掺合料 收缩开裂 

分 类 号：TU526[建筑科学—建筑技术科学]