蒸养温度对超细粉煤灰砂浆性能的影响研究  

Effect of different steam curing temperatures on ultrafine fly ash-cement mortar

作　　者：韦菲飞 Wei Feifei(Architectural Design and Research Institute of Xi'an University of Architecture and Technology,Xi'an,710055,China)

机构地区：[1]西安建筑科技大学设计研究总院有限公司,陕西西安710055

出　　处：《水泥工程》2024年第5期91-96,共6页Cement Engineering

摘　　要：为探讨不同蒸养温度下超细粉煤灰(UFA)-水泥砂浆的性能,分别研究了标养200℃、蒸养500℃、600℃和700℃下20%、30%、40%三种UFA掺量对UFA-水泥砂浆的流动性和力学性能的影响,并结合化学结合水量法、热重法(TG-DTG)分析了UFA-水泥复合胶凝材料的水化和UFA的作用效应。结果表明:UFA-水泥砂浆的流动性随UFA掺量的增大而增大;相同掺量下,蒸养与标养相比提高了UFA-水泥砂浆的早期强度;相同温度下500℃和600℃蒸养UFA试件的28 d抗折和抗压强度比纯水泥组低,700℃下UFA-20%的28 d抗折和抗压强度分别为10.0 MPa和53.1 MPa达到最大且高于纯水泥组;与1 d龄期相比,28 d龄期蒸养试件中的UFA参与水化反应明显,不同掺量的平均CH含量约为标养的90%,化学结合水量和热重结果显示蒸养促进了浆体水化程度并提高了UFA颗粒的火山灰活性。To investigate the performance of ultra-fine fly ash(UFA)cement mortar under different steam curing temperatures,the effects of 20%,30%,and 40%UFA admixtures on the flowability and mechanical properties of UFA cement mortar were studied at standard curing 20℃,steam curing 50℃,60℃,and 70℃,respectively.The hydration and UFA action effects of UFA cement composite cementitious materials were analyzed using chemical combined water content method and thermogravimetric method(TG-DTG).The results show that the flowability of UFA cement mortar increases with the increase of UFA content;Under the same dosage,steam curing improved the early strength of UFA cement mortar compared to standard curing;The 28d flexural and compressive strength of UFA specimens steamed at 50℃and 60℃at the same temperature is lower than that of the control group.The 28d flexural and compressive strength of UFA-20%at 70℃reaches its maximum at 10.0 MPa and 53.1 MPa,respectively,and is higher than that of the control group;Compared with the 1d age group,the UFA in the 28 d age group steam cured specimens participated significantly in the hydra⁃tion reaction,and steam cured promoted the degree of slurry hydration and increased the volcanic ash activity of UFA particles.

关 键 词：超细粉煤灰 蒸汽养护 化学结合水量 TG-DTG 

分 类 号：TQ172.6[化学工程—水泥工业]