非活性掺合料对大体积混凝土性能的影响  

Influence of inactive admixtures on the properties of mass concrete

作　　者：宋少民 蒋泽宇 SONG Shaomin;JIANG Zeyu(Green Building and Green City Key Technology Research and Application Innovation Team,Beijing Advanced Innovation Center for Future Urban Design,Beijing Key Laboratory of Building Structure and Environmental Remediation Functional Materials,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]北京建筑大学,建筑结构与环境修复功能材料北京市重点实验室,北京未来城市设计高精尖创新中心,绿色建筑和绿色城市关键技术研究与应用创新团队,北京100044

出　　处：《混凝土》2024年第9期145-149,156,共6页Concrete

摘　　要：大体积混凝土结构体量大,水化温升较高,在温度应力作用下极易形成裂缝对结构产生严重的危害。研究大掺量非活性掺合料对于降低混凝土水化热、推迟水化热温度峰值的出现时间和减少裂缝危害的技术效果。测试了3种非活性掺合料(白云石粉、石灰石粉和尾矿微粉)的相关技术指标,与50%掺量的粉煤灰混凝土对比,研究和分析了同掺量下3种非活性掺合料对大体积混凝土的绝热温升、力学性能和耐久性能的影响,同时通过超景深显微镜对其混凝土细观结构进行了观测。研究结果表明:大掺量非活性掺合料降低胶凝体系水化热的程度与粉煤灰相当,其配制的混凝土工作性能和耐久性能良好,各龄期混凝土强度稳定发展,可以有效控制大体积混凝土结构的裂缝产生,具有替代粉煤灰的应用前景。Large volume concrete structures are thick and massive,with high hydration temperature rise,which can easily form cracks to cause serious structure damage.It investigates the technical effects of large amounts of inactive admixtures on reducing the heat of hydration of concrete,delaying the onset of peak heat of hydration temperatures and reducing the risk of cracking.The technical specifications of three inactive admixtures(dolomite powder,limestone powder and tailings powder)were tested,and their effects on the adiabatic temperature rise,mechanical properties and durability of mass concrete were tested and analysed in 50%fly ash concrete.The fine structure was studied by the ultra-depth three-dimensional microscope.The results of the study show that the inactive admixtures reduce the heat of hydration of the cementitious system to an extent comparable to that of fly ash,resulting in concrete with good workability and durability,at different ages the compressive strength develops steadily.The inactive admixtures effectively slow down shrinkage and cracks in the concrete and reduce the adiabatic temperature rise of the concrete,have the application prospect to replace fly ash.

关 键 词：非活性掺合料 大体积混凝土 水化热 绝热温升 力学性能 耐久性 

分 类 号：TU528.01[建筑科学—建筑技术科学]