粉煤灰渣替代细骨料对砂浆混凝土强度及抗冻性影响  

Influence of Fly Ash Slag Substitution of Fine Aggregate on Strength and Frost Resistance of Mortar Concrete

作　　者：张卉 潘慧敏[1] 石雨轩 周美茹[2] 王冬丽 ZHANG Hui;PAN Huimin;SHI Yuxuan;ZHOU Meiru;WANG Dongli(Key Laboratory of Green Construction and Intelligent Operation of Civil Engineering of Hebei Province,Yanshan University,Qinhuangdao 066004,China;Hebei Green High-Performance Building Material Application Technology Collaborative Innovation Center,Hebei Construction 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,河北省绿色高性能建材应用技术协同创新中心,秦皇岛066004

出　　处：《硅酸盐通报》2022年第2期433-440,449,共9页Bulletin of the Chinese Ceramic Society

基　　金：河北省省级科技计划(19274103D);河北省自然科学基金(E2021107004)。

摘　　要：通过筛分和破碎两种方式分别获得粒径区间为0.6~1.18 mm、0.3~0.6 mm的粉煤灰渣,并用其等体积替代对应粒径区间的细骨料,分析粉煤灰渣对砂浆工作性和强度的影响,探究粉煤灰渣的最优替代粒径区间。结合扫描电镜(SEM)、能谱分析(EDS)等方法分析了粉煤灰渣替代细骨料后砂浆试件的强度变化机理。基于砂浆最优替代粒径区间结果,验证了砂浆混凝土试件的强度和抗冻性。研究结果表明:分别以筛分方式和破碎方式得到的0.3~0.6 mm粒径区间粉煤灰渣替代对应区间细骨料后,其砂浆试件强度均与基准组(未替代)基本一致;而以筛分方式得到的0.3~0.6 mm粒径区间粉煤灰渣替代对应区间细骨料后,其混凝土试件强度和抗冻性与基准组基本一致。在水泥提供的氢氧化钙环境下粉煤灰渣表面生成水化硅酸钙,从而增加了水泥和粉煤灰渣界面胶结强度,强化水泥与粉煤灰渣界面区域,凹凸不平的粉煤灰渣表面与水泥浆咬合嵌锁,保证了试件的强度。Through sieving and crushing,fly ash slag with the particle size range of 0.6 mm to 1.18 mm and 0.3 mm to 0.6 mm were obtained,respectively,and fine aggregate in the corresponding particle size range was replaced by the same volume of fly ash slag.The influence of fly ash slag on the workability and strength of mortar was analyzed,and the optimal alternative particle size range of fly ash slag was explored.Combined with scanning electron microscopy(SEM),energy dispersive spectrometer(EDS)and other methods,the strength change mechanism of mortar specimens after the replacement of fine aggregate by fly ash slag was analyzed.Based on the results of the optimal replacement particle size range of the mortar,the strength and frost resistance of the mortar concrete specimens were verified.The results show that:after sieving and crushing to obtain fly ash slag in the particle size range of 0.3 mm to 0.6 mm to replace the fine aggregate in this interval,the strength of the mortar specimens is the same as that of the benchmark group;sieving to obtain the fly ash slag in the particle size range of 0.3 mm to 0.6 mm to replace this interval,the strength and frost resistance of the concrete specimens are the same as those of the benchmark group.Under the calcium hydroxide environment provided by cement,calcium silicate hydrate is formed on the surface of fly ash slag,thereby increasing the cement and fly ash slag interface bonding strength,strengthening the interface area between the cement and the fly ash slag.The uneven surface is interlocked with the cement slurry to ensure the strength of the specimen.

关 键 词：粉煤灰渣 粒径区间 砂浆 混凝土 强度 抗冻性 微观形貌 

分 类 号：TU521[建筑科学—建筑技术科学]