预处理低质粉煤灰渣对砂浆使用性能和微观结构的影响  

Influence of Pretreatment of Low-quality Fly Ash Slag on Performance and Microstructure of Mortar

作　　者：杨泽政 赵庆新[1] 周美茹[2] YANG Ze-zheng;ZHAO Qing-xin;ZHOU Mei-ru(Key Laboratory of Green Construction and Intelligent Operation of Civil Engineering of Hebei Province,Yanshan University,Qinhuangdao 066004,China;Industry University ResearchCooperation Office,Hebei Building Materials Vocational and Technical College,Qinhuangdao 066004,China)

机构地区：[1]燕山大学河北省土木工程绿色建造与智能运维重点实验室,秦皇岛066004 [2]河北建材职业技术学院产学研合作处,秦皇岛066004

出　　处：《武汉理工大学学报》2021年第8期70-74,85,共6页Journal of Wuhan University of Technology

基　　金：河北省重点研发计划(19274103D).

摘　　要：为了提高低品质粉煤灰渣的利用率,通过对粉煤灰渣进行筛分和预湿等方式处理后替代机制砂,对比分析了粉煤灰渣以不同的粒度、掺入方式和替代率对砂浆流动性和力学性能的影响,并通过扫描电子显微镜(SEM)对砂浆90d龄期的微观结构进行分析。结果表明,砂浆流动性随粉煤灰渣对机制砂替代率的增加而增加;预湿的粉煤灰渣能够产生一定的内养护作用,促进粉煤灰渣附近水泥的水化;干掺时,水泥浆容易被大颗粒粉煤灰渣吸入内部,水化产物能够填充孔洞,在一定程度上降低孔隙率。干掺粒径小于2.36mm的粉煤灰渣,以10%替代机制砂的各项性能最优,90d龄期较基准组的抗折强度提高15%,抗压强度提高7%。In order to improve the utilization rate of low-quality fly ash slag,the fly ash slag was screened and pre-wetted to replace the machine-made sand,and the fly ash slag was compared and analyzed with different particle sizes,blending methods,and substitution rates.The influence on the fluidity and mechanical properties of the mortar,and the microstructure of the mortar at 90 dage were analyzed by scanning electron microscopy(SEM).The experimental results show that the fluidity of the mortar increases with the increase of the replacement rate of fly ash slag for machine-made sand.The pre-wet fly ash slag can produce a certain internal curing effect and promote the hydration of the cement near the fly ash slag.When dry blending,the cement slurry is easily sucked into the interior by large particles of fly ash slag,and the hydration products can fill the pores and reduce the porosity to a certain extent.Dry blending of fly ash slag with a particle size of less than 2.36 mm,replacing the machine-made sand with 10%has the best performance.Compared with the benchmark group,the flexural strength of the 90 dage group is increased by 15%,and the compressive strength is increased by7%.

关 键 词：粉煤灰渣 内养护 流动度 微观结构 

分 类 号：TQ177.6[化学工程—硅酸盐工业]