摘要
采用水泥固化的方式处理工程渣土会造成碳排放量提高、环境污染加剧的问题,为降低渣土处理中水泥用量,对工程应用中渣土处理提供可行性方案。采用固废材料脱硫石膏和硅粉协同水泥固化工程渣土,开展了不同液固比、不同固化材料掺量配比下的定量无侧限抗压强度试验、pH试验、X射线衍射试验(XRD)和电镜扫描试验(SEM),分析了改良渣土的无侧限抗压强度影响因素、微观结构发展规律及材料间协同固化的适用环境。结果表明,液固比的大小与固化渣土的无侧限抗压强度大小呈先增后减的相关性,且在0.2~0.3之间时效果最好。各配比下改良土浊液均呈碱性,随着浊液pH值增加,无侧限抗压强度不断增加,同配比试样随着养护龄期增加,浊液pH值不断降低。改良渣土随养护龄期增长,土体内部结构逐渐致密,形成针状、棒状物质的致密层大幅提升土体强度。研究结果可为我国工程渣土处理提供可选方案,亦为协同固化机理提供理论参考。
The use of cement solidification for the treatment of construction waste soil can lead to increased carbon e-missions and exacerbated environmental pollution.To reduce the amount of cement used in soil treatment and provide fea-sible solutions for engineering applications,this paper investigates the solidification of construction waste soil with waste materials such as desulfurized gypsum and silica fume in conjunction with cement.A series of tests were conducted,in-cluding unconfined compressive strength tests at various liquid-to-solid ratios and curing material mixtures,pH tests,X-ray diffraction(XRD)analyses,and scanning electron microscopy(SEM)examinations.The study analyzed the factors affecting the unconfined compressive strength of the improved soil,the development patterns of its microstructure,and the suitable environmental conditions for the synergistic solidification of materials.The results indicate that there is a pos-itive correlation between the liquid-to-solid ratio and the unconfined compressive strength of the solidified soil,which first increases and then decreases,with the best results obtained in the range of 0.2 to 0.3.The liquid from each mixture of the improved soil is alkaline,and as the pH of the liquid increases,so does the unconfined compressive strength.With the same mixture ratio,the pH of the liquid decreases over time as the curing period increases.As the curing age of the improved soil increases,the internal structure of the soil becomes denser,with the formation of dense layers of needle-like and rod-like substances significantly enhancing the soil's strength.The research results can offer alternative solutions for the treatment of construction waste soil in China and provide a theoretical reference for the synergistic solidification mech-anism.
作者
贺帅奇
贾沼霖
练继建
赵启翔
李更祥
HE Shuai-qi;JIA Zhao-lin;LIAN Ji-jian;ZHAO Qi-xiang;LI Geng-xiang(School of Water Resources and Hydropower,Hebei University of Engineering,Handan 056038,China;Hebei Key Laboratory of Intelligent Water Conservancy,Hebei University of Engineering,Handan 056038,China;China Huadian Corporation Limited,Beijing 100031,China)
出处
《水电能源科学》
北大核心
2025年第1期47-51,共5页
Water Resources and Power
关键词
脱硫石膏
硅粉
固化
无侧限抗压强度
微观结构
desulfurized gypsum
silicon powder
curing
unconfined compressive strength
microstructure
