摘要
针对机制砂(MS)表面粗糙、需水量大、早期强度低等性能缺陷,系统分析了掺偏高岭土(MK)与粉煤灰(FA)对机制砂混凝土力学性能及微观机理的影响规律。通过设计多组复合掺量方案,分析试件抗压强度随时间的变化规律,并结合扫描电子显微镜(SEM)分析微观机制。结果表明,复掺体系可协同优化性能,提高抗压强度。微观分析显示,掺合料通过微集料填充和火山灰反应,可细化孔隙结构,减少Ca(OH)_(2)晶体取向,改善界面过渡区密实度。研究还发现,机制砂石粉含量与掺合料存在交互作用。因此,偏高岭土与粉煤灰复掺可有效平衡机制砂混凝土的力学性能,为绿色高性能机制砂混凝土配合比设计提供理论依据。
A systematic analysis was conducted on the effects of adding metakaolin(MK)and fly ash(FA)on the mechanical properties and micro mechanisms of manufactured sand(MS)concrete,in response to its performance defects such as rough surface,high water demand,and low early strength.By designing multiple composite dosage schemes,analyzing the trend of compressive strength of specimens over time,and combining scanning electron microscopy(SEM)to analyze the microscopic mechanism.The results indicate that the composite system can synergistically optimize performance and improve compressive strength.Microscopic analysis showed that the admixture can refine the pore structure,reduce the orientation of Ca(OH)_(2) crystals,and improve the compactness of the interface transition zone through micro aggregate filling and volcanic ash reaction.The study also found that there was an interaction between the content of manufactured sand and gravel powder and the admixture.Therefore,the combination of metakaolin and fly ash can effectively balance the mechanical properties of manufactured sand concrete,providing a theoretical basis for the mix design of green high-performance mechanism sand concrete.
作者
周万东
杨硕
汤林
申辰启
ZHOU Wandong;YANG Shuo;TANG Lin;SHEN Chenqi(Shandong Road and Bridge Group Co.,Ltd.,Jinan Shandong 250002,China;School of Civil Engineering,Changchun Institute of Technology,Changchun Jilin 130012,China)
出处
《长春工程学院学报(自然科学版)》
2025年第4期72-77,共6页
Journal of Changchun Institute of Technology:Natural Science Edition
基金
山东省路桥集团有限公司科技研发项目(2024-SGS-JNEB-FW-003)。
