循环流化床飞灰对泡沫混凝土性能的影响  

Effect of Circulating Fluidized Bed Fly Ash on Performance of Foam Concrete

作　　者：陈盟 周明凯[1,2] 王杰 陈立顺 CHEN Meng;ZHOU Mingkai;WANG Jie;CHEN Lishun(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070 [2]武汉理工大学硅酸盐建筑材料国家重点实验室,武汉430070

出　　处：《硅酸盐通报》2023年第7期2447-2457,共11页Bulletin of the Chinese Ceramic Society

摘　　要：为了研究循环流化床(CFB)飞灰对泡沫混凝土性能的影响,选择两种不同的CFB飞灰以及普通粉煤灰(FA),通过测量泡沫混凝土的抗压强度、流动度、孔结构和吸水率,研究飞灰掺量和种类对泡沫混凝土性能的影响,并通过扫描电子显微镜和X射线衍射仪对泡沫混凝土的微观形貌和物相组成进行表征。结果表明,CFB飞灰较高的硫钙含量和不规则的颗粒形貌会对泡沫混凝土的工作性造成不良影响。掺入低硫钙型CFB飞灰时,泡沫混凝土的强度随着CFB飞灰掺量增加而提高,50%(质量分数,下同)掺量时,7和28 d抗压强度均达到最大值,分别为1.30和2.25 MPa;掺入高硫钙型CFB飞灰时,泡沫混凝土的强度随着CFB飞灰掺量增加呈先增加后降低的趋势,7和28 d抗压强度分别在CFB飞灰掺量20%和10%时达到最大值,分别为1.42和2.00 MPa。CFB飞灰水化过程中生成的钙钒石和C-S-H凝胶能够填充孔隙,增加小孔占比,降低孔隙率,有利于泡沫混凝土抗压强度的提高和吸水率的降低。In order to study the effect of circulating fluidized bed(CFB)fly ash on the performance of foam concrete,two different CFB fly ash and fly ash(FA)were selected,and the compressive strength,fluidity,pore structure and water absorption of foam concrete were measured.The influences of fly ash content and type on the properties of foam concrete were studied,and the micromorphology and phase composition of foam concrete were characterized by scanning electron microscopy and X-ray diffractometer.The results show that the high sulfur calcium content and irregular particle morphology of CFB fly ash will adversely affect the working performance of foam concrete.When low sulfur calcium CFB fly ash is added,the strength of foam concrete increases with the increase of CFB fly ash content,and the compressive strength of 7 and 28 d reaches the maximum value of 1.30 and 2.25 MPa at 50%(mass fraction,the same below)content.When high sulfur calcium CFB fly ash is added,the strength of foam concrete shows a trend of increasing first and then decreasing with the increase of CFB fly ash content,and the compressive strength of 7 and 28 d reaches the maximum value at 20%and 10%content,which is 1.42 and 2.00 MPa,respectively.The ettringite and C-S-H gel generated during the hydration process of CFB fly ash can fill the pores,increase the proportion of small pores,reduce the porosity,which is beneficial to increase compressive strength and reduce water absorption of foam concrete.

关 键 词：泡沫混凝土 CFB飞灰 钙钒石 抗压强度 微观形貌 

分 类 号：TU528.2[建筑科学—建筑技术科学]