摘要
研究了石灰、水泥掺量对循环流化床(CFB)粉煤灰-磷建筑石膏胶凝材料强度与耐水性能的影响,通过正交试验优化了CFB粉煤灰-水泥-石灰复合改性磷建筑石膏胶凝材料配合比,并采用X射线衍射(XRD)和扫描电镜(SEM)测试了改性石膏的水化产物和微观结构。结果表明,CFB粉煤灰掺量为10%时,较低掺量(1%-5%)的石灰能够明显增强CFB粉煤灰-磷建筑石膏胶凝材料强度,较高掺量(8%-12%)的水泥能够明显增强CFB粉煤灰-磷建筑石膏胶凝材料的耐水性能;经10%CFB粉煤灰、12%水泥和3%石灰复合改性,磷建筑石膏胶凝材料后期强度和耐水性能得到显著提高;复合改性石膏水化生成的水化硅酸钙(C-S-H)凝胶和钙矾石包裹并填充到二水硫酸钙晶体孔隙中,使得其水化产物孔结构得到优化,呈现出更致密的微观结构。
The influence of lime and cement content on the strength and water resistance of CFB fly ash-phosphorus building gypsum cementitious material were studied. The mix proportion of CFB fly ash-cement-lime composite modified phosphate building gypsum cementitious material was optimized through orthogonal test. Moreover, the hydration products and microstructure of the modified gypsum were tested by X-ray diffraction(XRD) and scanning electron microscope(SEM). The results showed that when the content of CFB fly ash was 10%, the lower content(1%-5%) of lime could significantly enhance the strength of CFB fly ash-phosphorus building gypsum cementitious material, and the higher content(8%-12%)of cement could significantly enhance the water resistance of CFB fly ash-phosphorus building gypsum cementitious material. The late strength and water resistance of phosphorus building gypsum cementitious material modified by 10% CFB fly ash, 12% cement and 3% lime had been significantly improved. Additionally, the C-S-H gel and ettringite generated by hydration of composite modified gypsum were wrapped and filled into the pores of the calcium sulfate dihydrate crystals, so that the pore structure of the hydrated product was optimized, showing a more compact microstructure.
作者
李龙
李北星
杨洋
Li Long;Li Beixing;Yang Yang(State Key Laboratory of Silicate Materials for Architecture,Wuhan University of Technology,Wuhan,Hubei 430070;Hubei Tianxin Building Materials Company Limited,Dangyang,Hubei 444100)
出处
《非金属矿》
CSCD
北大核心
2022年第1期102-106,共5页
Non-Metallic Mines
基金
国家重点研发计划(2020YFC1909904)。
关键词
磷建筑石膏
CFB粉煤灰
复合改性
水化
phosphorus building gypsum
CFB fly ash
composite modification
hydration
