摘要
将磷石膏作为水泥基充填材料替代胶凝材料,是一种有效的综合利用方式。目前对磷石膏掺入混凝土后的内部孔隙分布特征和碳化、抗渗等易导致结构失效的性能缺乏系统的研究。本文制备了6组不同磷石膏掺量的玄武岩纤维混凝土试件,并对其进行碳化和抗渗试验,结合XRD、SEM和比表面积及孔径分析研究了不同磷石膏掺量对玄武岩纤维混凝土碳化及抗渗性能的影响。结果表明,随着磷石膏掺量和碳化龄期的增加,玄武岩纤维混凝土的碳化深度增加,并且磷石膏掺量、碳化龄期和碳化深度三者之间存在函数关系。玄武岩纤维混凝土渗水高度随磷石膏掺量的增加呈先增长后下降的趋势。通过微观结构分析发现,随着磷石膏掺量的增加,玄武岩纤维混凝土比表面积及不同孔径的孔体积增长,钙钒石(AFt)生成量上升。总孔体积的增长导致早期碳化速率提高、渗水高度增长。AFt具有微膨胀性,与水化硅酸钙(C-S-H)凝胶的共同作用填充了部分孔隙通道,这不仅使玄武岩纤维混凝土后期碳化速率下降,在磷石膏掺量超过6%(质量分数)后渗水高度也出现下降,还使磷石膏掺量为15%(质量分数)的玄武岩纤维混凝土比表面积和不同孔径的孔体积下降。研究成果为进一步丰富和完善磷石膏资源利用技术提供了可参考的资料。
The use of phosphogypsum as a cement-based filling material to replace cementitious materials is an effective comprehensive utilization.At present,there is a lack of systematic research on the internal pore distribution characteristics and the properties of carbonation and seepage resistance of phosphogypsum incorporated into concrete,which can easily lead to structural failure.In this paper,six groups of basalt fiber concrete specimens with different proportions of phosphogypsum content were prepared and tested for carbonation and seepage resistance,and the effect of different phosphogypsum content on the carbonation and seepage resistance of basalt fiber concrete was investigated by combining with XRD,SEM,and specific surface area and pore size analysis.The results show that the carbonation depth of basalt fiber concrete increases with the increase of phosphogypsum content and carbonation age,and there is a functional relationship between phosphogypsum content,carbonation age and carbonation depth.The water penetration height of basalt fiber concrete shows a trend of increasing first and then decreasing with the increase of phosphogypsum content.The microstructural analysis reveals that with the increase of phosphogypsum content,the specific surface area of basalt fiber concrete and pore volume of different pore sizes increase,and the amount of ettringite(AFt)increases.The increase of total pore volume leads to the increase of carbonation rate and water penetration height growth in the early stage.AFt has micro-expansion property,and the joint action of AFt and C-S-H gel to fill up some of the pore channels,which not only lead to the decrease of carbonation rate in the late stage of basalt fiber concrete,and the decrease of water penetration height in the phosphogypsum content more than 6%(mass fraction),but also lead to the decrease of specific surface area and pore volume of different pore sizes of basalt fiber concrete with 15%(mass fraction)phosphogypsum.The research results provide reference information for further enrichment and improvement of phosphogypsum resource utilization technology.
作者
罗国仪
徐桂弘
任旭
邓文波
陈孜伟
刘次啟
LUO Guoyi;XU Guihong;REN Xu;DENG Wenbo;CHEN Ziwei;LIU Ciqi(College of Civil Engineering,Guizhou University,Guiyang 550025,China;School of Civil Engineering,Guizhou Institute of Technology,Guiyang 550003,China;Chongqing Rail Transit(Group)Co.,Ltd.,Chongqing 401120,China;Guizhou Building Materials Product Quality Inspection and Testing Institute,Guiyang 550014,China)
出处
《硅酸盐通报》
北大核心
2025年第1期231-242,共12页
Bulletin of the Chinese Ceramic Society
基金
贵州省科技计划项目(黔科合基础-ZK[2022]重点027)
贵阳市科技计划项目(筑科合同[2024]-1-8)
贵州省高层次创新型人才项目(黔科合平台人才-GCC[2023]053)。
关键词
磷石膏
玄武岩纤维混凝土
碳化
抗渗性能
微观机理
比表面积分析
孔径分析
phosphogypsum
basalt fiber concrete
carbonation
seepage resistance
micromechanism
specific surface area analysis
pore size analysis
