摘要
以过硫磷石膏(PPG)、矿渣、粉煤灰和水泥熟料作为胶凝材料,通过调整过硫磷石膏的占比,制备出一系列过硫磷石膏固废混凝土,系统研究了过硫磷石膏掺杂量对固废混凝土力学性能、物相结构、水化反应速率以及抗碳化性能的影响。结果表明,过硫磷石膏固废混凝土的磷元素溶出量符合水体污染国家排放标准,随着过硫磷石膏占比的增加,混凝土在前期的水化过程更加温和,减少了因水化反应过快而导致的自收缩,加速了二次水化的进行,累积放热量增加。PPG-46%试样在168 h时的自收缩率达到了最小值1856μm/m,在7 d时相对湿度达到最大值87.8%。随着过硫磷石膏掺杂比例的增加,在养护龄期28 d时,混凝土的抗压强度和抗折强度先增大后轻微降低,PPG-46%试样的抗压强度和抗折强度达到最大值,分别为66.62和6.08 MPa。当碳化35 d时,PPG-46%试样碳化面积超过了50%,碳化深度最低为9.8 mm,抗碳化性能最佳。
A series of perphosphorus gypsum solid waste concrete were prepared by adjusting the proportion of perphosphorus gypsum(PPG),and using PPG,slag,fly ash and cement clinker as cementitious materials.The influence of the doping amount of perphosphorus gypsum on the mechanical properties,phase structure,hydration reaction rate and carbonation resistance of solid waste concrete was studied.The results showed that the phosphorus leaching amount of perphosphorus gypsum solid waste concrete meets the national discharge standards for water pollution.With the increase of the proportion of perphosphorus gypsum,the hydration process of concrete in the early stage became milder,reducing the self shrinkage caused by rapid hydration reaction,accelerating the secondary hydration process,and increasing the accumulated heat release.The self shrinkage rate of the PPG-46%sample reached its minimum value of 1856μm/m at 168 h,and the relative humidity reached its maximum value of 87.8%at 7 d.With the increase of the proportion of perphosphorus gypsum doping,the compressive strength and flexural strength of the concrete first increased and then slightly decreased at a curing age of 28 d.The compressive strength and flexural strength of the PPG-46%sample reached their maximum values,which were 66.62 and 6.08 MPa,respectively.When carbonized for 35 d,the carbonization area of the PPG-46%sample exceeded 50%,and the lowest carbonization depth was 9.8 mm,indicating the best carbonization resistance.
作者
高丹丹
孟睿君
秦春丽
刘学瑞
张鸿
GAO Dandan;MENG Ruijun;QIN Chunli;LIU Xuerui;ZHANG Hong(School of Architectural Engineering,Zhengzhou University of Industrial Technology,Zhengzhou 451100,China;School of Materials Science and Engineering,Chang'an University,Xi'an 710000,China)
出处
《功能材料》
北大核心
2025年第8期8219-8227,共9页
Journal of Functional Materials
基金
国家自然科学基金项目(61403271)。
关键词
过硫磷石膏
固废混凝土
力学性能
水化反应
碳化性能
perphosphorus gypsum
solid waste concrete
mechanical properties
hydration reaction
carbonization performance
